Macros for declaring commands, arguments, options, subcommands, lifecycle hooks, param groups, and validation.
Summary
Functions
Set the command's description text, shown in help output.
Set text displayed after the auto-generated help.
Run a function on the result after run/2. Receives and returns result.
Set subcommand aliases (e.g. aliases ["co", "ck"] for checkout).
Declare a positional argument.
Set text displayed before the auto-generated help.
Run a function on args before run/2. Receives and returns args map.
Define a command block with the given name.
Define a named group of options with a constraint.
Set the command's extended description, shown by --help (long form).
Declare a named option (flag).
Like before_run, but inherited by all child subcommands.
Propagate this command's version to all subcommands.
Register a child subcommand module.
Require that a subcommand is provided (error instead of showing help).
Declare a named trailing variable argument.
Override the auto-generated usage line in help output.
Cross-parameter validation function. Receives args map, returns :ok or {:error, msg}.
Set the command's version string, printed by --version / -V.
Functions
Set the command's description text, shown in help output.
Set text displayed after the auto-generated help.
Run a function on the result after run/2. Receives and returns result.
Set subcommand aliases (e.g. aliases ["co", "ck"] for checkout).
Declare a positional argument.
Arguments are matched in declaration order. Options:
:type-:string(default),:integer,:float, or:boolean:required-trueorfalse(default):help- help text shown in--help:long_help- extended help text shown by--help(long form):value_name- placeholder name in help (e.g."FILE"):hide-trueto hide from help output:validate-fn value -> :ok | {:error, msg} end
Set text displayed before the auto-generated help.
Run a function on args before run/2. Receives and returns args map.
Define a command block with the given name.
All DSL calls (about, argument, option, subcommand, etc.) go inside the block.
command "deploy" do
about "Deploy the app"
option :env, type: :string, required: true
endDefine a named group of options with a constraint.
Supports:
mutually_exclusive: true-- at most one option in the group can be setco_occurring: true-- all or none of the options must be set
Set the command's extended description, shown by --help (long form).
Declare a named option (flag).
Options:
:type-:string(default),:integer,:float,:boolean, or:count:short- single-character alias atom (e.g.:pfor-p):required-trueorfalse(default):default- default value when not provided (:countdefaults to0,:multidefaults to[]):multi-trueto allow repeated flags collected into a list (e.g.--tag a --tag b):env- environment variable name to read as fallback:choices- list of allowed values:help- help text shown in--help:long_help- extended help text shown by--help(long form):value_name- placeholder name in help (e.g."FILE"):hide-trueto hide from help output:global-trueto propagate to all subcommands:aliases- list of alternative long names (e.g.[:colour]for:color):validate-fn value -> :ok | {:error, msg} end
Boolean options automatically support --no-<name> negation (e.g. --no-color).
Extra positional arguments after -- are collected into args[:rest].
Like before_run, but inherited by all child subcommands.
Propagate this command's version to all subcommands.
Register a child subcommand module.
Require that a subcommand is provided (error instead of showing help).
Declare a named trailing variable argument.
Everything after the last declared positional (or after --) is collected
and available as args[name] instead of the default :rest key. The name
and help text are shown in the usage and help output.
Options:
:help- help text shown in--help:required-trueif at least one trailing arg must be provided
Override the auto-generated usage line in help output.
Cross-parameter validation function. Receives args map, returns :ok or {:error, msg}.
Set the command's version string, printed by --version / -V.