Add README.md generation, closes #4

README.md

@@ -1,4 +1,6 @@
-# Bash Command Template
+# Bash Template Command
+
+*This `README.md` is [autogenerated](#generate-readme-md-file).*
 
 This is a GitHub template repo that will be copied instead of forked to
 create a new Bash command with a command something like this:
@@ -7,16 +9,13 @@ create a new Bash command with a command something like this:
 gh repo create rwxrob/mycmd -p rwxrob/template-bash-command
 ```
 
+This `command` inside can then be renamed and finished.
+
 Obviously, not all of this is needed for many Bash scripts, but anything
 with more than two subcommands will benefit from the builtin tab
 completion, embedded Markdown help documentation support, and included
 functions (`usage`, `_filter`, `_buffer`, `_have`, etc.)
 
-## Installation
-
-It's usually easiest to install by cloning the repo and adding the full
-path to this repo to your `PATH`. That way you can keep up with updates.
-
 ## Naming Conventions
 
 * Name repos containing single bash commands with `cmd-`
@@ -24,52 +23,6 @@ path to this repo to your `PATH`. That way you can keep up with updates.
 * Start command functions with `command_` to be completed
 * Start command functions with `command__` to not be completed
 
-## Usage
-
-```
-command
-command usage
-command help [<cmd>]
-command foo [<arg>]
-command bar [<arg>]
-```
-
-## Commands
-
-|  Command    | Summary                                                |
-|    :-:      | -                                                      |
-|  [usage]    | Display single line summary of all command usage |
-|  [help]     | Display help information |
-|  [foo]      | Do the foo |
-|  [bar]      | Do the bar |
-
-[usage]: #usage
-[help]: #help
-[foo]: #foo
-[bar]: #bar
-
-### `usage`
-
-The `usage` command displays a summary of usage.
-
-### `help`
-
-The help command prints help information. If no argument is passed
-displays general help information (main). Otherwise, the documentation
-for the specific argument keyword is displayed, which usually
-corresponds to a command name (but not necessarily). All documentation
-is written in CommonMark (Markdown) and will displayed as Web page if
-`pandoc` and `$HELP_BROWSER` are detected, otherwise, just the Markdown is
-sent to `$PAGER` (default: `more`).
-
-### `foo`
-
-The `foo` command foos.
-
-### `bar`
-
-The `bar` command bars.
-
 ## Dependencies
 
 Required:
@@ -107,3 +60,45 @@ Copyright 2021 Rob Muhlestein <rob@rwx.gg>
 Released under Apache-2.0 License  
 Please mention <https://youtube.com/rwxrob>
 
+----
+
+## Commands
+
+### The `bar` Command
+
+Bars.
+
+### The `foo` Command
+
+Foos.
+
+### Display Help Information
+
+```
+help [<command>]
+```
+
+Displays specific help information. If no argument is passed displays
+general help information (main). Otherwise, the documentation for the
+specific argument keyword is displayed, which usually corresponds to
+a command name (but not necessarily). All documentation is written in
+GitHub Flavored Markdown and will displayed as a web page if `pandoc`
+and `$HELP_BROWSER` are detected, otherwise, just the Markdown is sent
+to `$PAGER` (default: more).
+
+Also see `readme` and `usage` commands.
+
+### Generate `README.md` File
+
+```
+command readme > README.md
+```
+
+The `readme` command will output the embedded help documentation in raw
+GitHub Flavored Markdown suitable for use as a `README.md` file on
+GitHub or similar hosting service.
+
+### The `usage` Command
+
+Displays a summary of usage.
+

command

@@ -1,11 +1,7 @@
 #!/usr/bin/bash
 # shellcheck disable=SC2016
 set -e
-export PATH="/usr/bin:/usr/local/bin"
+# export PATH="/usr/bin:/usr/local/bin" # safer, if you can
-
-# Copyright 2021 Rob Muhlestein <rob@rwx.gg>
-# Released under Apache-2.0 license
-# Please mention https://youtube.com/rwxrob
 
 (( BASH_VERSINFO[0] < 4 )) && echo "Bash 4+ required." && exit 1
 
@@ -18,27 +14,78 @@ EXE="${0##*/}"
 declare -A help # associative arrays *require* declaration
 
 help[main]='
-# Sample Bash Template Command
+# Bash Template Command
 
-This `command` contains the scaffolding for Bash tab completion using
+*This `README.md` is autogenerated.*
-the `complete -C foo foo` variation which allows scripts to complete
-themselves (rather than having another script somewhere to manage). To
-use it simply add a function with the additional command and add the
-name of it to the commands array declaration at the top of the script.
-Then add `complete -C foo foo` to your bashrc.  Begin functions with
-`command_` to allow useful command names to be used that would otherwise
-conflict with existing system and bash keywords.  Begin functions with
-`command__` when you do not want them to appear with tab completion, but
-still want them to be available, just hidden.'
 
-help[foo]='The `foo` command foos.'
+This is a GitHub template repo that will be copied instead of forked to
+create a new Bash command with a command something like this:
+
+```
+gh repo create rwxrob/mycmd -p rwxrob/template-bash-command
+```
+
+This `command` inside can then be renamed and finished.
+
+Obviously, not all of this is needed for many Bash scripts, but anything
+with more than two subcommands will benefit from the builtin tab
+completion, embedded Markdown help documentation support, and included
+functions (`usage`, `_filter`, `_buffer`, `_have`, etc.)
+
+## Naming Conventions
+
+* Name repos containing single bash commands with `cmd-`
+* Name template repos beginning with `template-`
+* Start command functions with `command_` to be completed
+* Start command functions with `command__` to not be completed
+
+## Dependencies
+
+Required:
+
+* Bash 4+
+
+Optional:
+
+* `pandoc` - for rich help docs
+
+## Justification
+
+Bash is the dominate shell scripting language and the official default
+Linux interactive shell, which reduces cognitive overhead; every command
+line *is* a line of code that could be put into script as is. Bash
+scripts are at the core of cloud, containers, and Kubernetes. Bash 4+
+with its associative array support, powerful regular expressions, and
+multiple ways of feeding data to loops easily covers the needs
+previously requiring Python and Perl scripts. Bash scripts are also much
+more powerful, safer, flexible, and performant than POSIX shell or Zsh.
+
+## Caveats
+
+* Use the official bash path: `#!/usr/bin/bash`
+* Using `#!/usr/bin/env bash` introduces unnecessary risk
+* Always set the acceptable `PATH` at beginning of script
+* Always check script with [`shellcheck`] before releasing
+* Always use `bc` for *any* floating point math
+
+[`shellcheck`]: <https://www.shellcheck.net>
+
+## Legal
+
+Copyright 2021 Rob Muhlestein <rob@rwx.gg>  
+Released under Apache-2.0 License  
+Please mention <https://youtube.com/rwxrob>  
+
+'
+
+help[foo]='Foos.'
 
 command_foo() {
   _filter "$@" && return $?
   echo "would foo: $*"
 }
 
-help[bar]='The `bar` command bars.'
+help[bar]='Bars.'
 
 command_bar() {
   _buffer "$@" && return $?
@@ -50,7 +97,7 @@ command__hidden() {
   echo "would run _hidden: $*"
 }
 
-help[usage]='The `usage` command displays a summary of usage.'
+help[usage]='Displays a summary of usage.'
 
 command_usage() {
   local -a cmds
@@ -63,27 +110,25 @@ command_usage() {
 }
 
 help[help]='
-# The `help` Command
+# Display Help Information
 
-The `help` command prints help information. If no argument is passed
+```
-displays general help information (main). Otherwise, the documentation
+help [<command>]
-for the specific argument keyword is displayed, which usually
+```
-corresponds to a command name (but not necessarily). All documentation
+
-is written in CommonMark (Markdown) and will displayed as Web page if
+Displays specific help information. If no argument is passed displays
-`pandoc` and `$HELP_BROWSER` are detected, otherwise, just the Markdown is
+general help information (main). Otherwise, the documentation for the
-sent to `$PAGER` (default: more).'
+specific argument keyword is displayed, which usually corresponds to
+a command name (but not necessarily). All documentation is written in
+GitHub Flavored Markdown and will displayed as a web page if `pandoc`
+and `$HELP_BROWSER` are detected, otherwise, just the Markdown is sent
+to `$PAGER` (default: more).
+
+Also see `readme` and `usage` commands.
+'
 
 command_help() { 
-  local name="$1"
+  local name="${1:-main}" title own body
-  if [[ -z "$name" ]];then
-    for c in "${COMMANDS[@]}";do
-      [[ ${c:0:1} = _ ]] && continue;
-      command_help "$c" buildonly || true
-    done
-    command_help main
-    return 0
-  fi
-  local title own body
   title=$(_help_title "$name")
   if [[ -z "$title" ]]; then
     body="${help[$name]}"
@@ -109,6 +154,30 @@ command_help() {
   echo -e "$title\n\n$body" | "$PAGER"
 }
 
+help[readme]='
+# Generate `README.md` File
+
+```
+command readme > README.md
+```
+
+The `readme` command will output the embedded help documentation in raw
+GitHub Flavored Markdown suitable for use as a `README.md` file on
+GitHub or similar hosting service.  '
+
+command_readme() {
+  _trim "${help[main]}"
+  local usage="$(command_usage)"
+  printf "\n----\n\n## Commands\n\n"
+  local -a names=("${!help[@]}")
+  while IFS= read -r name; do
+    [[ $name = main ]] && continue
+    local body=$(_trim "${help[$name]}")
+    [[ $body =~ ^\# ]] || body="# The \`$name\` Command\n\n$body"
+    printf "##$body\n\n"
+  done < <(printf "%s\n" "${!help[@]}" | LC_COLLATE=C sort)
+}
+
 # --------------------- completion and delegation --------------------
 #         (better than . <(foo bloated_completion) in .bashrc)
 
@@ -122,6 +191,11 @@ _help_title() {
   done <<< "${help[$name]}"
 }
 
+_trim() {
+  local it="${1#"${1%%[![:space:]]*}"}"
+  echo -e "${it%"${it##*[![:space:]]}"}"
+}
+
 _have(){ type "$1" &>/dev/null; }
 
 _filter(){
@@ -140,6 +214,7 @@ while IFS= read -r line; do
   [[ $line =~ ^declare\ -f\ command_ ]] || continue
   COMMANDS+=( "${line##declare -f command_}" )
 done < <(declare -F)
+COMMANDS=($(LC_COLLATE=C sort < <(printf "%s\n" "${COMMANDS[@]}")))
 
 if [[ -n $COMP_LINE ]]; then
   line=${COMP_LINE#* }