Update README

DavidGamba · Jan 5, 2024 · 26ca3e2 · 26ca3e2
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@@ -330,9 +330,9 @@ Only the last two versions of Go will be supported.
 
 NOTE: For a <<quick_overview>>, jump to that section in the TOC or review the http://godoc.org/github.com/DavidGamba/go-getoptions[GoDoc Documentation].
 
-Option parsing is the act of taking command line arguments and converting them into meaningful structures within the program.
+Option parsing is the act of taking command line (CLI) arguments and converting them into meaningful structures within the program.
 
-First declare a getoptions instance:
+First declare a `getoptions` instance:
 
 [source, go]
 ----
@@ -472,6 +472,186 @@ func Name(ctx context.Context, opt *getoptions.GetOpt, args []string) error {
 }
 ----
 
+== Automatically generate help
+
+For a proper extended man page for your program consider link:http://asciidoctor.org/[asciidoctor] that can generate manpages written in the Asciidoc markup.
+
+For the built-in help, you can add a description to your program:
+
+- `opt.Self("", "This is a program description")`
+
+NOTE: When the first argument is empty, it will use the program name from `os.Args[0]`.
+
+For options help ensure you add option descriptions and argument names.
+
+- `opt.Description("This is a string option")`
+- `opt.ArgName("mystring")`
+
+The help command needs to be defined after all options, commands and subcommands.
+
+`opt.HelpCommand("help", opt.Alias("?"))`
+
+When calling the help command, you get the full help.
+Optionally you can print only given sections of the Help.
+
+For example:
+
+[source, go]
+----
+fmt.Fprintf(os.Stderr, "%s", opt.Help(getoptions.HelpSynopsis))
+----
+
+Or through a helper:
+
+[source, go]
+----
+func ForceUnlock(ctx context.Context, opt *getoptions.GetOpt, args []string) error {
+	lockID, args, err := opt.GetRequiredArg(args)
+	if err != nil {
+		return err
+	}
+----
+
+In the code above, if there is no argument passed, the `GetRequiredArg` will print an error plus the synopsis:
+
+----
+ERROR: Missing <lock-id>
+SYNOPSIS:
+    program [--help] <lock-id>
+----
+
+The error return is `getoptions.ErrorHelpCalled` which signals the help is already printed.
+The dispatch error handling can handle this error and not print and additional error message.
+
+
+[source, go]
+----
+	err = opt.Dispatch(ctx, remaining)
+	if err != nil {
+		if errors.Is(err, getoptions.ErrorHelpCalled) {
+			return 1
+		}
+		fmt.Fprintf(os.Stderr, "ERROR: %s\n", err)
+		if errors.Is(err, getoptions.ErrorParsing) {
+			fmt.Fprintf(os.Stderr, "\n"+opt.Help())
+		}
+		return 1
+	}
+	return 0
+----
+
+Another helpful error to check for is `getoptions.ErrorParsing`, as shown above, which indicates there was a problem parsing the CLI arguments.
+This can be used, to print the help only in cases where the user didn't enter valid CLI options or arguments.
+
+The built in help shows default values and environment variables when available.
+
+It separates required parameters from options.
+
+For example, the following is a script using the built in help:
+
+----
+$ bt terraform force-unlock help
+NAME:
+    bt terraform force-unlock
+
+SYNOPSIS:
+    bt terraform force-unlock [--help|-?] [--profile <string>] [--quiet]
+                              [--ws <string>] <lock-id>
+
+ARGUMENTS:
+    <lock-id>             Lock ID
+
+OPTIONS:
+    --help|-?             (default: false)
+
+    --profile <string>    BT Terraform Profile to use (default: "default", env: AWS_PROFILE)
+
+    --quiet               (default: false, env: QUIET)
+
+    --ws <string>         Workspace to use (default: "")
+----
+
+And below is the output of the automated help of a program with multiple commands:
+
+----
+$ tz help
+SYNOPSIS:
+    tz [--config|-c <string>] [--format-standard|--format-12-hour|--format-12h]
+       [--group <string>] [--help|-?] [--short|-s] [--verbose] <command> [<args>]
+
+COMMANDS:
+    cities     filter cities list
+    list       list all timezones
+    version    show version
+
+OPTIONS:
+    --config|-c <string>                               Config file (default: "")
+
+    --format-standard|--format-12-hour|--format-12h    Use standard 12 hour AM/PM time format (default: false)
+
+    --group <string>                                   Group to show (default: "")
+
+    --help|-?                                          (default: false)
+
+    --short|-s                                         Don't show timezone bars (default: false)
+
+    --verbose                                          Enable logging (default: false, env: TZ_VERBOSE)
+
+Use 'tz help <command>' for extra details.
+----
+
+Any built-in string in `go-getoptions`, like titles, is exposed as a public variable so it can be overridden for internationalization.
+
+== Autocompletion
+
+To enable bash autocompletion, add the following line to your bash profile:
+
+[source,bash]
+----
+complete -o default -C my-go-program my-go-program
+----
+
+For the above to work, the program must be in the PATH.
+Otherwise:
+
+[source,bash]
+----
+complete -o default -C "$HOME/go/bin/my-go-program" my-go-program
+----
+
+To enable zsh autocompletion, add the following line to your zsh profile:
+
+[source,zsh]
+----
+export ZSHELL="true"
+autoload -U +X compinit && compinit
+autoload -U +X bashcompinit && bashcompinit
+complete -o default -C my-go-program my-go-program
+----
+
+The `ZSHELL="true"` export is required because bash and zsh have different ways of handling autocompletion and there is no reliable way to detect which shell is being used.
+
+If testing completion in the CLI, you might require to first clean the completion entry that `complete` auto generates when hitting `Tab` twice:
+
+`complete -r ./my-go-program 2>/dev/null`
+
+When providing these as scripts that users source but not add into their profile you can use the following `sourceme.bash` script:
+
+.sourceme.bash
+[source,bash]
+----
+#!/bin/bash
+
+# Remove existing entries to ensure the right one is loaded
+# This is not required when the completion one liner is loaded in your bashrc.
+complete -r ./my-go-program 2>/dev/null
+
+complete -o default -C "$PWD/my-go-program" my-go-program
+----
+
+Then when the users go into the directory and run `source sourceme.bash` the autocompletion will be enabled.
+
+
 === Boolean options
 
 Opposite of default when passed on the command line.
@@ -744,7 +924,7 @@ When calling `CommandFn` directly, it is sometimes useful to set the option as c
 Use cases are for testing and wrappers.
 
 [[operation_modes]]
-== Operation Modes
+== Operation Modes: How to handle single dash '-' options
 
 Notice how so far only long options (options starting with double dash `--`) have been mentioned.
 There are 3 main ways to handle short options (options starting with only one dash `-`).
@@ -818,185 +998,6 @@ a|option: `"o"`, argument: `"pt=arg"` footnote:[Argument gets type casted depend
 
 |===
 
-== Automatically generate help
-
-For a proper extended man page for your program consider link:http://asciidoctor.org/[asciidoctor] that can generate manpages written in the Asciidoc markup.
-
-For the built-in help, you can add a description to your program:
-
-- `opt.Self("", "This is a program description")`
-
-NOTE: When the first argument is empty, it will use the program name from `os.Args[0]`.
-
-For options help ensure you add option descriptions and argument names.
-
-- `opt.Description("This is a string option")`
-- `opt.ArgName("mystring")`
-
-The help command needs to be defined after all options, commands and subcommands.
-
-`opt.HelpCommand("help", opt.Alias("?"))`
-
-When calling the help command, you get the full help.
-Optionally you can print only given sections of the Help.
-
-For example:
-
-[source, go]
-----
-fmt.Fprintf(os.Stderr, "%s", opt.Help(getoptions.HelpSynopsis))
-----
-
-Or through a helper:
-
-[source, go]
-----
-func ForceUnlock(ctx context.Context, opt *getoptions.GetOpt, args []string) error {
-	lockID, args, err := opt.GetRequiredArg(args)
-	if err != nil {
-		return err
-	}
-----
-
-In the code above, if there is no argument passed, the `GetRequiredArg` will print an error plus the synopsis:
-
-----
-ERROR: Missing <lock-id>
-SYNOPSIS:
-    program [--help] <lock-id>
-----
-
-The error return is `getoptions.ErrorHelpCalled` which signals the help is already printed.
-The dispatch error handling can handle this error and not print and additional error message.
-
-
-[source, go]
-----
-	err = opt.Dispatch(ctx, remaining)
-	if err != nil {
-		if errors.Is(err, getoptions.ErrorHelpCalled) {
-			return 1
-		}
-		fmt.Fprintf(os.Stderr, "ERROR: %s\n", err)
-		if errors.Is(err, getoptions.ErrorParsing) {
-			fmt.Fprintf(os.Stderr, "\n"+opt.Help())
-		}
-		return 1
-	}
-	return 0
-----
-
-Another helpful error to check for is `getoptions.ErrorParsing`, as shown above, which indicates there was a problem parsing the CLI arguments.
-This can be used, to print the help only in cases where the user didn't enter valid CLI options or arguments.
-
-The built in help shows default values and environment variables when available.
-
-It separates required parameters from options.
-
-For example, the following is a script using the built in help:
-
-----
-$ bt terraform force-unlock help
-NAME:
-    bt terraform force-unlock
-
-SYNOPSIS:
-    bt terraform force-unlock [--help|-?] [--profile <string>] [--quiet]
-                              [--ws <string>] <lock-id>
-
-ARGUMENTS:
-    <lock-id>             Lock ID
-
-OPTIONS:
-    --help|-?             (default: false)
-
-    --profile <string>    BT Terraform Profile to use (default: "default", env: AWS_PROFILE)
-
-    --quiet               (default: false, env: QUIET)
-
-    --ws <string>         Workspace to use (default: "")
-----
-
-And below is the output of the automated help of a program with multiple commands:
-
-----
-$ tz help
-SYNOPSIS:
-    tz [--config|-c <string>] [--format-standard|--format-12-hour|--format-12h]
-       [--group <string>] [--help|-?] [--short|-s] [--verbose] <command> [<args>]
-
-COMMANDS:
-    cities     filter cities list
-    list       list all timezones
-    version    show version
-
-OPTIONS:
-    --config|-c <string>                               Config file (default: "")
-
-    --format-standard|--format-12-hour|--format-12h    Use standard 12 hour AM/PM time format (default: false)
-
-    --group <string>                                   Group to show (default: "")
-
-    --help|-?                                          (default: false)
-
-    --short|-s                                         Don't show timezone bars (default: false)
-
-    --verbose                                          Enable logging (default: false, env: TZ_VERBOSE)
-
-Use 'tz help <command>' for extra details.
-----
-
-Any built-in string in `go-getoptions`, like titles, is exposed as a public variable so it can be overridden for internationalization.
-
-== Autocompletion
-
-To enable bash autocompletion, add the following line to your bash profile:
-
-[source,bash]
-----
-complete -o default -C my-go-program my-go-program
-----
-
-For the above to work, the program must be in the PATH.
-Otherwise:
-
-[source,bash]
-----
-complete -o default -C "$HOME/go/bin/my-go-program" my-go-program
-----
-
-To enable zsh autocompletion, add the following line to your zsh profile:
-
-[source,zsh]
-----
-export ZSHELL="true"
-autoload -U +X compinit && compinit
-autoload -U +X bashcompinit && bashcompinit
-complete -o default -C my-go-program my-go-program
-----
-
-The `ZSHELL="true"` export is required because bash and zsh have different ways of handling autocompletion and there is no reliable way to detect which shell is being used.
-
-If testing completion in the CLI, you might require to first clean the completion entry that `complete` auto generates when hitting `Tab` twice:
-
-`complete -r ./my-go-program 2>/dev/null`
-
-When providing these as scripts that users source but not add into their profile you can use the following `sourceme.bash` script:
-
-.sourceme.bash
-[source,bash]
-----
-#!/bin/bash
-
-# Remove existing entries to ensure the right one is loaded
-# This is not required when the completion one liner is loaded in your bashrc.
-complete -r ./my-go-program 2>/dev/null
-
-complete -o default -C "$PWD/my-go-program" my-go-program
-----
-
-Then when the users go into the directory and run `source sourceme.bash` the autocompletion will be enabled.
-
 == Command behaviour
 
 This section describes how the parser resolves ambiguities between the program and the command.