Add importable_sw.fish and add example to swim.fish

importable_sw.fish

@@ -0,0 +1,87 @@
+#!/usr/bin/env fish
+set -g cmd_func_prefix 'swim'
+
+function main
+    run_swim_command $cmd_func_prefix $argv
+end
+
+function run_swim_command -a prefix
+    argparse --ignore-unknown 'h/help' -- $argv
+    set -l command $argv[2]
+    set -l func $prefix\_$command
+    set -l args $argv[3..-1]
+
+    define_included_functions $prefix
+
+    if functions -q $func
+        if test -n "$_flag_h"
+            if test ($func is_group) = 'is-group' >/dev/null 2>&1
+                $func $args --help
+            else
+                $prefix\_help $command
+            end
+        else
+            $func $args
+        end
+    else if test -n "$_flag_h"
+        $prefix\_help
+    else if functions -q $prefix\_default
+        $prefix\_default $args
+    else
+        echo "$prefix command '$command' does not exist"
+        return 127
+    end
+end
+
+function define_included_functions -a prefix
+    set -l prefix $prefix
+
+    function $prefix\_do -V prefix -d 'Perform a list of commands separated by commas'
+        for command in (string split ',' "$argv")
+            test -z "$command"; and continue
+            set -l command (string trim "$command")
+
+            echo "Running '$command' ..."
+            run_swim_command $prefix (string split ' ' $command)
+        end
+    end
+
+    function _$prefix\_commands -V prefix -d 'List all available commands'
+        set -l names (functions --names | grep "^$prefix\_")
+
+        for name in $names
+            set -l details (functions -D -v $name)
+            set -l description $details[5]
+            set -l short_name (string replace $prefix\_ '' $name)
+
+            if test (string length $short_name) -ge 8
+                echo $short_name\t$description
+            else
+                echo $short_name\t\t$description
+            end
+        end
+    end
+
+    function $prefix\_help -a command -V prefix -d 'Print help menu or command definition'
+        if test -n "$command"
+            functions $prefix\_$command
+        else
+            echo 'Here are the available commands:'\n
+            _$prefix\_commands
+            echo \n"To see a command's definition do `run help {command}`"
+            echo "To see a subcommand group's help menu do `run {command} help`"
+        end
+    end
+
+    if not functions -q $prefix\_default
+        function $prefix\_default -a arg -V prefix -d 'Alias for help command'
+            $prefix\_help $arg
+        end
+    end
+
+    function $prefix\_is_group -d 'Tells executor whether this is a subcommand group'
+        echo 'is-group'
+    end
+end
+
+main $argv

swim.fish

@@ -70,3 +70,6 @@ end
 function swim_fails -d 'This command fails every time'
     false
 end
+
+# Uncomment the following to import the execution code for swim.fish, and run it like `./swim.fish`.
+# curl -fsS https://raw.githubusercontent.com/mitchell/swim.fish/master/importable_sw.fish | source