778 lines
29 KiB
Plaintext
778 lines
29 KiB
Plaintext
'\"
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'\" Copyright (c) 1993 The Regents of the University of California.
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'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
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'\" Copyright (c) 1993-1997 Bell Labs Innovations for Lucent Technologies
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'\" Copyright (c) 1998-2000 Ajuba Solutions
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'\" Copyright (c) 2007-2012 Donal K. Fellows
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'\"
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'\" See the file "license.terms" for information on usage and redistribution
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'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
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'\"
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.TH info n 8.4 Tcl "Tcl Built-In Commands"
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.so man.macros
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.BS
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'\" Note: do not modify the .SH NAME line immediately below!
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.SH NAME
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info \- Return information about the state of the Tcl interpreter
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.SH SYNOPSIS
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\fBinfo \fIoption \fR?\fIarg arg ...\fR?
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.BE
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.SH DESCRIPTION
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.PP
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This command provides information about various internals of the Tcl
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interpreter.
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The legal \fIoption\fRs (which may be abbreviated) are:
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.TP
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\fBinfo args \fIprocname\fR
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.
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Returns a list containing the names of the arguments to procedure
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\fIprocname\fR, in order. \fIProcname\fR must be the name of a
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Tcl command procedure.
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.TP
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\fBinfo body \fIprocname\fR
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.
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Returns the body of procedure \fIprocname\fR. \fIProcname\fR must be
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the name of a Tcl command procedure.
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.TP
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\fBinfo class\fI subcommand class\fR ?\fIarg ...\fR
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.VS 8.6
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Returns information about the class, \fIclass\fR. The \fIsubcommand\fRs are
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described in \fBCLASS INTROSPECTION\fR below.
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.VE 8.6
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.TP
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\fBinfo cmdcount\fR
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.
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Returns a count of the total number of commands that have been invoked
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in this interpreter.
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.TP
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\fBinfo commands \fR?\fIpattern\fR?
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.
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If \fIpattern\fR is not specified,
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returns a list of names of all the Tcl commands visible
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(i.e. executable without using a qualified name) to the current namespace,
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including both the built-in commands written in C and
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the command procedures defined using the \fBproc\fR command.
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If \fIpattern\fR is specified,
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only those names matching \fIpattern\fR are returned.
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Matching is determined using the same rules as for \fBstring match\fR.
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\fIpattern\fR can be a qualified name like \fBFoo::print*\fR.
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That is, it may specify a particular namespace
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using a sequence of namespace names separated by double colons (\fB::\fR),
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and may have pattern matching special characters
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at the end to specify a set of commands in that namespace.
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If \fIpattern\fR is a qualified name,
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the resulting list of command names has each one qualified with the name
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of the specified namespace, and only the commands defined in the named
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namespace are returned.
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.\" Technically, most of this hasn't changed; that's mostly just the
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.\" way it always worked. Hardly anyone knew that though.
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.TP
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\fBinfo complete \fIcommand\fR
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.
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Returns 1 if \fIcommand\fR is a complete Tcl command in the sense of
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having no unclosed quotes, braces, brackets or array element names.
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If the command does not appear to be complete then 0 is returned.
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This command is typically used in line-oriented input environments
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to allow users to type in commands that span multiple lines; if the
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command is not complete, the script can delay evaluating it until additional
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lines have been typed to complete the command.
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.TP
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\fBinfo coroutine\fR
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.VS 8.6
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Returns the name of the currently executing \fBcoroutine\fR, or the empty
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string if either no coroutine is currently executing, or the current coroutine
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has been deleted (but has not yet returned or yielded since deletion).
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.VE 8.6
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.TP
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\fBinfo default \fIprocname arg varname\fR
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.
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\fIProcname\fR must be the name of a Tcl command procedure and \fIarg\fR
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must be the name of an argument to that procedure. If \fIarg\fR
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does not have a default value then the command returns \fB0\fR.
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Otherwise it returns \fB1\fR and places the default value of \fIarg\fR
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into variable \fIvarname\fR.
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.TP
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\fBinfo errorstack \fR?\fIinterp\fR?
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.VS 8.6
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Returns, in a form that is programmatically easy to parse, the function names
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and arguments at each level from the call stack of the last error in the given
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\fIinterp\fR, or in the current one if not specified.
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.RS
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.PP
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This form is an even-sized list alternating tokens and parameters. Tokens are
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currently either \fBCALL\fR, \fBUP\fR, or \fBINNER\fR, but other values may be
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introduced in the future. \fBCALL\fR indicates a procedure call, and its
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parameter is the corresponding \fBinfo level\fR \fB0\fR. \fBUP\fR indicates a
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shift in variable frames generated by \fBuplevel\fR or similar, and applies to
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the previous \fBCALL\fR item. Its parameter is the level offset. \fBINNER\fR
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identifies the
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.QW "inner context" ,
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which is the innermost atomic command or bytecode instruction that raised the
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error, along with its arguments when available. While \fBCALL\fR and \fBUP\fR
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allow to follow complex call paths, \fBINNER\fR homes in on the offending
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operation in the innermost procedure call, even going to sub-expression
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granularity.
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.PP
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This information is also present in the \fB\-errorstack\fR entry of the
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options dictionary returned by 3-argument \fBcatch\fR; \fBinfo errorstack\fR
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is a convenient way of retrieving it for uncaught errors at top-level in an
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interactive \fBtclsh\fR.
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.RE
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.VE 8.6
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.TP
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\fBinfo exists \fIvarName\fR
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.
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Returns \fB1\fR if the variable named \fIvarName\fR exists in the
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current context (either as a global or local variable) and has been
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defined by being given a value, returns \fB0\fR otherwise.
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.TP
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\fBinfo frame\fR ?\fInumber\fR?
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.
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This command provides access to all frames on the stack, even those
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hidden from \fBinfo level\fR. If \fInumber\fR is not specified, this
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command returns a number giving the frame level of the command. This
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is 1 if the command is invoked at top-level. If \fInumber\fR is
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specified, then the result is a dictionary containing the location
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information for the command at the \fInumber\fRed level on the stack.
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.RS
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.PP
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If \fInumber\fR is positive (> 0) then it selects a particular stack
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level (1 refers to the outer-most active command, 2 to the command it
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called, and so on, up to the current frame level which refers to
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\fBinfo frame\fR itself); otherwise it gives a level relative to the
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current command (0 refers to the current command, i.e., \fBinfo
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frame\fR itself, -1 to its caller, and so on).
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.PP
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This is similar to how \fBinfo level\fR works, except that this
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subcommand reports all frames, like \fBsource\fRd scripts,
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\fBeval\fRs, \fBuplevel\fRs, etc.
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.PP
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Note that for nested commands, like
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.QW "foo [bar [x]]" ,
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only
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.QW x
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will be seen by an \fBinfo frame\fR invoked within
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.QW x .
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This is the same as for \fBinfo level\fR and error stack traces.
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.PP
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The result dictionary may contain the keys listed below, with the
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specified meanings for their values:
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.TP
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\fBtype\fR
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.
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This entry is always present and describes the nature of the location
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for the command. The recognized values are \fBsource\fR, \fBproc\fR,
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\fBeval\fR, and \fBprecompiled\fR.
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.RS
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.TP
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\fBsource\fR\0\0\0\0\0\0\0\0
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.
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means that the command is found in a script loaded by the \fBsource\fR
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command.
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.TP
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\fBproc\fR\0\0\0\0\0\0\0\0
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.
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means that the command is found in dynamically created procedure body.
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.TP
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\fBeval\fR\0\0\0\0\0\0\0\0
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.
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means that the command is executed by \fBeval\fR or \fBuplevel\fR.
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.TP
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\fBprecompiled\fR\0\0\0\0\0\0\0\0
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.
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means that the command is found in a pre-compiled script (loadable by
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the package \fBtbcload\fR), and no further information will be
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available.
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.RE
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.TP
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\fBline\fR
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.
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This entry provides the number of the line the command is at inside of
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the script it is a part of. This information is not present for type
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\fBprecompiled\fR. For type \fBsource\fR this information is counted
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relative to the beginning of the file, whereas for the last two types
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the line is counted relative to the start of the script.
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.TP
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\fBfile\fR
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.
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This entry is present only for type \fBsource\fR. It provides the
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normalized path of the file the command is in.
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.TP
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\fBcmd\fR
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.
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This entry provides the string representation of the command. This is
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usually the unsubstituted form, however for commands which are a
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canonically-constructed list (e.g., as produced by the \fBlist\fR command)
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executed by \fBeval\fR it is the substituted form as they have no other
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string representation. Care is taken that the canonicality property of
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the latter is not spoiled.
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.TP
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\fBproc\fR
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.
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This entry is present only if the command is found in the body of a
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regular Tcl procedure. It then provides the name of that procedure.
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.TP
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\fBlambda\fR
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.
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This entry is present only if the command is found in the body of an
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anonymous Tcl procedure, i.e. a lambda. It then provides the entire
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definition of the lambda in question.
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.TP
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\fBlevel\fR
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.
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This entry is present only if the queried frame has a corresponding
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frame returned by \fBinfo level\fR. It provides the index of this
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frame, relative to the current level (0 and negative numbers).
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.PP
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A thing of note is that for procedures statically defined in files the
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locations of commands in their bodies will be reported with type
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\fBsource\fR and absolute line numbers, and not as type
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\fBproc\fR. The same is true for procedures nested in statically
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defined procedures, and literal eval scripts in files or statically
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defined procedures.
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.PP
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In contrast, procedure definitions and \fBeval\fR within a dynamically
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\fBeval\fRuated environment count line numbers relative to the start of
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their script, even if they would be able to count relative to the
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start of the outer dynamic script. That type of number usually makes
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more sense.
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.PP
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A different way of describing this behaviour is that file based
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locations are tracked as deeply as possible, and where this is not
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possible the lines are counted based on the smallest possible
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\fBeval\fR or procedure body, as that scope is usually easier to find
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than any dynamic outer scope.
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.PP
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The syntactic form \fB{*}\fR is handled like \fBeval\fR. I.e. if it
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is given a literal list argument the system tracks the line number
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within the list words as well, and otherwise all line numbers are
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counted relative to the start of each word (smallest scope)
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.RE
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.TP
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\fBinfo functions \fR?\fIpattern\fR?
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.
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If \fIpattern\fR is not specified, returns a list of all the math
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functions currently defined.
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If \fIpattern\fR is specified, only those functions whose name matches
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\fIpattern\fR are returned. Matching is determined using the same
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rules as for \fBstring match\fR.
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.TP
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\fBinfo globals \fR?\fIpattern\fR?
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.
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If \fIpattern\fR is not specified, returns a list of all the names
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of currently-defined global variables.
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Global variables are variables in the global namespace.
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If \fIpattern\fR is specified, only those names matching \fIpattern\fR
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are returned. Matching is determined using the same rules as for
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\fBstring match\fR.
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.TP
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\fBinfo hostname\fR
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.
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Returns the name of the computer on which this invocation is being
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executed.
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Note that this name is not guaranteed to be the fully qualified domain
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name of the host. Where machines have several different names (as is
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common on systems with both TCP/IP (DNS) and NetBIOS-based networking
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installed,) it is the name that is suitable for TCP/IP networking that
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is returned.
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.TP
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\fBinfo level\fR ?\fInumber\fR?
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.
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If \fInumber\fR is not specified, this command returns a number
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giving the stack level of the invoking procedure, or 0 if the
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command is invoked at top-level. If \fInumber\fR is specified,
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then the result is a list consisting of the name and arguments for the
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procedure call at level \fInumber\fR on the stack. If \fInumber\fR
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is positive then it selects a particular stack level (1 refers
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to the top-most active procedure, 2 to the procedure it called, and
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so on); otherwise it gives a level relative to the current level
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(0 refers to the current procedure, -1 to its caller, and so on).
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See the \fBuplevel\fR command for more information on what stack
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levels mean.
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.TP
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\fBinfo library\fR
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.
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Returns the name of the library directory in which standard Tcl
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scripts are stored.
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This is actually the value of the \fBtcl_library\fR
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variable and may be changed by setting \fBtcl_library\fR.
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.TP
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\fBinfo loaded \fR?\fIinterp\fR?
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.
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Returns a list describing all of the packages that have been loaded into
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\fIinterp\fR with the \fBload\fR command.
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Each list element is a sub-list with two elements consisting of the
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name of the file from which the package was loaded and the name of
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the package.
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For statically-loaded packages the file name will be an empty string.
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If \fIinterp\fR is omitted then information is returned for all packages
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loaded in any interpreter in the process.
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To get a list of just the packages in the current interpreter, specify
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an empty string for the \fIinterp\fR argument.
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.TP
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\fBinfo locals \fR?\fIpattern\fR?
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.
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If \fIpattern\fR is not specified, returns a list of all the names
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of currently-defined local variables, including arguments to the
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current procedure, if any.
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Variables defined with the \fBglobal\fR, \fBupvar\fR and
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\fBvariable\fR commands will not be returned.
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If \fIpattern\fR is specified, only those names matching \fIpattern\fR
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are returned. Matching is determined using the same rules as for
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\fBstring match\fR.
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.TP
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\fBinfo nameofexecutable\fR
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.
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Returns the full path name of the binary file from which the application
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was invoked. If Tcl was unable to identify the file, then an empty
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string is returned.
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.TP
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\fBinfo object\fI subcommand object\fR ?\fIarg ...\fR
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.VS 8.6
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Returns information about the object, \fIobject\fR. The \fIsubcommand\fRs are
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described in \fBOBJECT INTROSPECTION\fR below.
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.VE 8.6
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.TP
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\fBinfo patchlevel\fR
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.
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Returns the value of the global variable \fBtcl_patchLevel\fR, which holds
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the exact version of the Tcl library by default.
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.TP
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\fBinfo procs \fR?\fIpattern\fR?
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.
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If \fIpattern\fR is not specified, returns a list of all the
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names of Tcl command procedures in the current namespace.
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If \fIpattern\fR is specified,
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only those procedure names in the current namespace
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matching \fIpattern\fR are returned.
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Matching is determined using the same rules as for
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\fBstring match\fR.
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If \fIpattern\fR contains any namespace separators, they are used to
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select a namespace relative to the current namespace (or relative to
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the global namespace if \fIpattern\fR starts with \fB::\fR) to match
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within; the matching pattern is taken to be the part after the last
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namespace separator.
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.TP
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\fBinfo script\fR ?\fIfilename\fR?
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.
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If a Tcl script file is currently being evaluated (i.e. there is a
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call to \fBTcl_EvalFile\fR active or there is an active invocation
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of the \fBsource\fR command), then this command returns the name
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of the innermost file being processed. If \fIfilename\fR is specified,
|
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then the return value of this command will be modified for the
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duration of the active invocation to return that name. This is
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useful in virtual file system applications.
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Otherwise the command returns an empty string.
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.TP
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\fBinfo sharedlibextension\fR
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.
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Returns the extension used on this platform for the names of files
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containing shared libraries (for example, \fB.so\fR under Solaris).
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If shared libraries are not supported on this platform then an empty
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string is returned.
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.TP
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\fBinfo tclversion\fR
|
|
.
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|
Returns the value of the global variable \fBtcl_version\fR, which holds the
|
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major and minor version of the Tcl library by default.
|
|
.TP
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\fBinfo vars\fR ?\fIpattern\fR?
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|
.
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If \fIpattern\fR is not specified,
|
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returns a list of all the names of currently-visible variables.
|
|
This includes locals and currently-visible globals.
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|
If \fIpattern\fR is specified, only those names matching \fIpattern\fR
|
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are returned. Matching is determined using the same rules as for
|
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\fBstring match\fR.
|
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\fIpattern\fR can be a qualified name like \fBFoo::option*\fR.
|
|
That is, it may specify a particular namespace
|
|
using a sequence of namespace names separated by double colons (\fB::\fR),
|
|
and may have pattern matching special characters
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at the end to specify a set of variables in that namespace.
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If \fIpattern\fR is a qualified name,
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the resulting list of variable names
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has each matching namespace variable qualified with the name
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of its namespace.
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Note that a currently-visible variable may not yet
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.QW exist
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if it has not
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been set (e.g. a variable declared but not set by \fBvariable\fR).
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.SS "CLASS INTROSPECTION"
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.VS 8.6
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.PP
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|
The following \fIsubcommand\fR values are supported by \fBinfo class\fR:
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.VE 8.6
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.TP
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\fBinfo class call\fI class method\fR
|
|
.VS
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|
Returns a description of the method implementations that are used to provide a
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|
stereotypical instance of \fIclass\fR's implementation of \fImethod\fR
|
|
(stereotypical instances being objects instantiated by a class without having
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any object-specific definitions added). This consists of a list of lists of
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four elements, where each sublist consists of a word that describes the
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general type of method implementation (being one of \fBmethod\fR for an
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ordinary method, \fBfilter\fR for an applied filter, and \fBunknown\fR for a
|
|
method that is invoked as part of unknown method handling), a word giving the
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name of the particular method invoked (which is always the same as
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|
\fImethod\fR for the \fBmethod\fR type, and
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.QW \fBunknown\fR
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|
for the \fBunknown\fR type), a word giving the fully qualified name of the
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class that defined the method, and a word describing the type of method
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implementation (see \fBinfo class methodtype\fR).
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.RS
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.PP
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|
Note that there is no inspection of whether the method implementations
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actually use \fBnext\fR to transfer control along the call chain.
|
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.RE
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.VE 8.6
|
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.TP
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\fBinfo class constructor\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns a description of the definition of the constructor of
|
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class \fIclass\fR. The definition is described as a two element list; the first
|
|
element is the list of arguments to the constructor in a form suitable for
|
|
passing to another call to \fBproc\fR or a method definition, and the second
|
|
element is the body of the constructor. If no constructor is present, this
|
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returns the empty list.
|
|
.VE 8.6
|
|
.TP
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\fBinfo class definition\fI class method\fR
|
|
.VS 8.6
|
|
This subcommand returns a description of the definition of the method named
|
|
\fImethod\fR of class \fIclass\fR. The definition is described as a two element
|
|
list; the first element is the list of arguments to the method in a form
|
|
suitable for passing to another call to \fBproc\fR or a method definition, and
|
|
the second element is the body of the method.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class destructor\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns the body of the destructor of class \fIclass\fR. If no
|
|
destructor is present, this returns the empty string.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class filters\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns the list of filter methods set on the class.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class forward\fI class method\fR
|
|
.VS 8.6
|
|
This subcommand returns the argument list for the method forwarding called
|
|
\fImethod\fR that is set on the class called \fIclass\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class instances\fI class\fR ?\fIpattern\fR?
|
|
.VS 8.6
|
|
This subcommand returns a list of instances of class \fIclass\fR. If the
|
|
optional \fIpattern\fR argument is present, it constrains the list of returned
|
|
instances to those that match it according to the rules of \fBstring match\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class methods\fI class\fR ?\fIoptions...\fR?
|
|
.VS 8.6
|
|
This subcommand returns a list of all public (i.e. exported) methods of the
|
|
class called \fIclass\fR. Any of the following \fIoption\fRs may be
|
|
specified, controlling exactly which method names are returned:
|
|
.RS
|
|
.VE 8.6
|
|
.TP
|
|
\fB\-all\fR
|
|
.VS 8.6
|
|
If the \fB\-all\fR flag is given, the list of methods will include those
|
|
methods defined not just by the class, but also by the class's superclasses
|
|
and mixins.
|
|
.VE 8.6
|
|
.TP
|
|
\fB\-private\fR
|
|
.VS 8.6
|
|
If the \fB\-private\fR flag is given, the list of methods will also include
|
|
the private (i.e. non-exported) methods of the class (and superclasses and
|
|
mixins, if \fB\-all\fR is also given).
|
|
.RE
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class methodtype\fI class method\fR
|
|
.VS 8.6
|
|
This subcommand returns a description of the type of implementation used for
|
|
the method named \fImethod\fR of class \fIclass\fR. When the result is
|
|
\fBmethod\fR, further information can be discovered with \fBinfo class
|
|
definition\fR, and when the result is \fBforward\fR, further information can
|
|
be discovered with \fBinfo class forward\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class mixins\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns a list of all classes that have been mixed into the
|
|
class named \fIclass\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class subclasses\fI class\fR ?\fIpattern\fR?
|
|
.VS 8.6
|
|
This subcommand returns a list of direct subclasses of class \fIclass\fR. If
|
|
the optional \fIpattern\fR argument is present, it constrains the list of
|
|
returned classes to those that match it according to the rules of
|
|
\fBstring match\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class superclasses\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns a list of direct superclasses of class \fIclass\fR in
|
|
inheritance precedence order.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo class variables\fI class\fR
|
|
.VS 8.6
|
|
This subcommand returns a list of all variables that have been declared for
|
|
the class named \fIclass\fR (i.e. that are automatically present in the
|
|
class's methods, constructor and destructor).
|
|
.SS "OBJECT INTROSPECTION"
|
|
.PP
|
|
The following \fIsubcommand\fR values are supported by \fBinfo object\fR:
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object call\fI object method\fR
|
|
.VS 8.6
|
|
Returns a description of the method implementations that are used to provide
|
|
\fIobject\fR's implementation of \fImethod\fR. This consists of a list of
|
|
lists of four elements, where each sublist consists of a word that describes
|
|
the general type of method implementation (being one of \fBmethod\fR for an
|
|
ordinary method, \fBfilter\fR for an applied filter, and \fBunknown\fR for a
|
|
method that is invoked as part of unknown method handling), a word giving the
|
|
name of the particular method invoked (which is always the same as
|
|
\fImethod\fR for the \fBmethod\fR type, and
|
|
.QW \fBunknown\fR
|
|
for the \fBunknown\fR type), a word giving what defined the method (the fully
|
|
qualified name of the class, or the literal string \fBobject\fR if the method
|
|
implementation is on an instance), and a word describing the type of method
|
|
implementation (see \fBinfo object methodtype\fR).
|
|
.RS
|
|
.PP
|
|
Note that there is no inspection of whether the method implementations
|
|
actually use \fBnext\fR to transfer control along the call chain.
|
|
.RE
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object class\fI object\fR ?\fIclassName\fR?
|
|
.VS 8.6
|
|
If \fIclassName\fR is unspecified, this subcommand returns class of the
|
|
\fIobject\fR object. If \fIclassName\fR is present, this subcommand returns a
|
|
boolean value indicating whether the \fIobject\fR is of that class.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object definition\fI object method\fR
|
|
.VS 8.6
|
|
This subcommand returns a description of the definition of the method named
|
|
\fImethod\fR of object \fIobject\fR. The definition is described as a two
|
|
element list; the first element is the list of arguments to the method in a
|
|
form suitable for passing to another call to \fBproc\fR or a method definition,
|
|
and the second element is the body of the method.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object filters\fI object\fR
|
|
.VS 8.6
|
|
This subcommand returns the list of filter methods set on the object.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object forward\fI object method\fR
|
|
.VS 8.6
|
|
This subcommand returns the argument list for the method forwarding called
|
|
\fImethod\fR that is set on the object called \fIobject\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object isa\fI category object\fR ?\fIarg\fR?
|
|
.VS 8.6
|
|
This subcommand tests whether an object belongs to a particular category,
|
|
returning a boolean value that indicates whether the \fIobject\fR argument
|
|
meets the criteria for the category. The supported categories are:
|
|
.VE 8.6
|
|
.RS
|
|
.TP
|
|
\fBinfo object isa class\fI object\fR
|
|
.VS 8.6
|
|
This returns whether \fIobject\fR is a class (i.e. an instance of
|
|
\fBoo::class\fR or one of its subclasses).
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object isa metaclass\fI object\fR
|
|
.VS 8.6
|
|
This returns whether \fIobject\fR is a class that can manufacture classes
|
|
(i.e. is \fBoo::class\fR or a subclass of it).
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object isa mixin\fI object class\fR
|
|
.VS 8.6
|
|
This returns whether \fIclass\fR is directly mixed into \fIobject\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object isa object\fI object\fR
|
|
.VS 8.6
|
|
This returns whether \fIobject\fR really is an object.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object isa typeof\fI object class\fR
|
|
.VS 8.6
|
|
This returns whether \fIclass\fR is the type of \fIobject\fR (i.e. whether
|
|
\fIobject\fR is an instance of \fIclass\fR or one of its subclasses, whether
|
|
direct or indirect).
|
|
.RE
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object methods\fI object\fR ?\fIoption...\fR?
|
|
.VS 8.6
|
|
This subcommand returns a list of all public (i.e. exported) methods of the
|
|
object called \fIobject\fR. Any of the following \fIoption\fRs may be
|
|
specified, controlling exactly which method names are returned:
|
|
.RS
|
|
.VE 8.6
|
|
.TP
|
|
\fB\-all\fR
|
|
.VS 8.6
|
|
If the \fB\-all\fR flag is given, the list of methods will include those
|
|
methods defined not just by the object, but also by the object's class and
|
|
mixins, plus the superclasses of those classes.
|
|
.VE 8.6
|
|
.TP
|
|
\fB\-private\fR
|
|
.VS 8.6
|
|
If the \fB\-private\fR flag is given, the list of methods will also include
|
|
the private (i.e. non-exported) methods of the object (and classes, if
|
|
\fB\-all\fR is also given).
|
|
.RE
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object methodtype\fI object method\fR
|
|
.VS 8.6
|
|
This subcommand returns a description of the type of implementation used for
|
|
the method named \fImethod\fR of object \fIobject\fR. When the result is
|
|
\fBmethod\fR, further information can be discovered with \fBinfo object
|
|
definition\fR, and when the result is \fBforward\fR, further information can
|
|
be discovered with \fBinfo object forward\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object mixins\fI object\fR
|
|
.VS 8.6
|
|
This subcommand returns a list of all classes that have been mixed into the
|
|
object named \fIobject\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object namespace\fI object\fR
|
|
.VS 8.6
|
|
This subcommand returns the name of the internal namespace of the object named
|
|
\fIobject\fR.
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object variables\fI object\fR
|
|
.VS 8.6
|
|
This subcommand returns a list of all variables that have been declared for
|
|
the object named \fIobject\fR (i.e. that are automatically present in the
|
|
object's methods).
|
|
.VE 8.6
|
|
.TP
|
|
\fBinfo object vars\fI object\fR ?\fIpattern\fR?
|
|
.VS 8.6
|
|
This subcommand returns a list of all variables in the private namespace of
|
|
the object named \fIobject\fR. If the optional \fIpattern\fR argument is
|
|
given, it is a filter (in the syntax of a \fBstring match\fR glob pattern)
|
|
that constrains the list of variables returned. Note that this is different
|
|
from the list returned by \fBinfo object variables\fR; that can include
|
|
variables that are currently unset, whereas this can include variables that
|
|
are not automatically included by any of \fIobject\fR's methods (or those of
|
|
its class, superclasses or mixins).
|
|
.VE 8.6
|
|
.SH EXAMPLES
|
|
.PP
|
|
This command prints out a procedure suitable for saving in a Tcl
|
|
script:
|
|
.PP
|
|
.CS
|
|
proc printProc {procName} {
|
|
set result [list proc $procName]
|
|
set formals {}
|
|
foreach var [\fBinfo args\fR $procName] {
|
|
if {[\fBinfo default\fR $procName $var def]} {
|
|
lappend formals [list $var $def]
|
|
} else {
|
|
# Still need the list-quoting because variable
|
|
# names may properly contain spaces.
|
|
lappend formals [list $var]
|
|
}
|
|
}
|
|
puts [lappend result $formals [\fBinfo body\fR $procName]]
|
|
}
|
|
.CE
|
|
.SS "EXAMPLES WITH OBJECTS"
|
|
.VS 8.6
|
|
.PP
|
|
Every object necessarily knows what its class is; this information is
|
|
trivially extractable through introspection:
|
|
.PP
|
|
.CS
|
|
oo::class create c
|
|
c create o
|
|
puts [\fBinfo object class\fR o]
|
|
\fI\(-> prints "::c"\fR
|
|
puts [\fBinfo object class\fR c]
|
|
\fI\(-> prints "::oo::class"\fR
|
|
.CE
|
|
.PP
|
|
The introspection capabilities can be used to discover what class implements a
|
|
method and get how it is defined. This procedure illustrates how:
|
|
.PP
|
|
.CS
|
|
proc getDef {obj method} {
|
|
foreach inf [\fBinfo object call\fR $obj $method] {
|
|
lassign $inf calltype name locus methodtype
|
|
# Assume no forwards or filters, and hence no $calltype
|
|
# or $methodtype checks...
|
|
if {$locus eq "object"} {
|
|
return [\fBinfo object definition\fR $obj $name]
|
|
} else {
|
|
return [\fBinfo class definition\fR $locus $name]
|
|
}
|
|
}
|
|
error "no definition for $method"
|
|
}
|
|
.CE
|
|
.PP
|
|
This is an alternate way of looking up the definition; it is implemented by
|
|
manually scanning the list of methods up the inheritance tree. This code
|
|
assumes that only single inheritance is in use, and that there is no complex
|
|
use of mixed-in classes (in such cases, using \fBinfo object call\fR as above
|
|
is the simplest way of doing this by far):
|
|
.PP
|
|
.CS
|
|
proc getDef {obj method} {
|
|
if {$method in [\fBinfo object methods\fR $obj]} {
|
|
# Assume no forwards
|
|
return [\fBinfo object definition\fR $obj $method]
|
|
}
|
|
set cls [\fBinfo object class\fR $obj]
|
|
while {$method ni [\fBinfo class methods\fR $cls]} {
|
|
# Assume the simple case
|
|
set cls [lindex [\fBinfo class superclass\fR $cls] 0]
|
|
if {$cls eq ""} {
|
|
error "no definition for $method"
|
|
}
|
|
}
|
|
# Assume no forwards
|
|
return [\fBinfo class definition\fR $cls $method]
|
|
}
|
|
.CE
|
|
.VE 8.6
|
|
.SH "SEE ALSO"
|
|
.VS 8.6
|
|
global(n), oo::class(n), oo::define(n), oo::object(n), proc(n), self(n),
|
|
.VE 8.6
|
|
tcl_library(n), tcl_patchLevel(n), tcl_version(n)
|
|
.SH KEYWORDS
|
|
command, information, interpreter, introspection, level, namespace,
|
|
.VS 8.6
|
|
object,
|
|
.VE 8.6
|
|
procedure, variable
|
|
'\" Local Variables:
|
|
'\" mode: nroff
|
|
'\" fill-column: 78
|
|
'\" End:
|