object

command_line_options

Command line options parsing predicates. Uses object-based option specifications with the command_line_option category.

Availability:

logtalk_load(command_line_options(loader))

Author: Marcus Uneson and Paulo Moura

Version: 1:1:0

Date: 2026-07-13

Compilation flags:

static, context_switching_calls

Imports:

public options

Uses:

atom

list

meta

numberlist

term_io

type

user

Remarks:

(none)

Inherited public predicates:

 check_option/1  check_options/1  default_option/1  default_options/1  option/2  option/3  valid_option/1  valid_options/1

Public predicates

parse/4

Parses the arguments AppArguments according to the option objects OptionObjects using default parsing options.

Compilation flags:

static

Template:

parse(OptionObjects,AppArguments,Options,PositionalArguments)

Mode and number of proofs:

parse(+list(object),+list(atom),-list,-list(atom)) - one_or_error

Exceptions:

OptionObjects is a variable, a partial list, or contains an option object definition with an insufficiently instantiated value:

instantiation_error

OptionObjects is neither a variable nor a list of valid object identifiers:

type_error(list(object),OptionObjects)

An option object is missing the name/1 predicate:

existence_error(predicate,name/1)

An option object predicate returns a value with an invalid type:

type_error(Type,Term)

An option object predicate returns a value outside the expected domain:

domain_error(Domain,Term)

The option set contains a duplicate option name:

domain_error(unique_key,Name)

The option set contains a duplicate short flag:

domain_error(unique_short_flag,ShortFlag)

The option set contains a duplicate long flag:

domain_error(unique_long_flag,LongFlag)

AppArguments is a variable or a partial list:

instantiation_error

AppArguments is neither a variable nor a list of atoms:

type_error(list(atom),AppArguments)

An unknown flag is found:

existence_error(command_line_option,Argument)

A flag value cannot be parsed as the option type:

type_error(flag_value,Type)

A short option is written using the disallowed -f=value syntax:

syntax_error(disallowed: <shortflag>=<value>)

---

parse/5

Parses the arguments AppArguments according to the option objects OptionObjects and the parsing options ParseOptions. Options is a list of parsed options as Name(Value) terms by default (or Func(Name,Value) when the output_functor(Func) parse option is used). PositionalArguments are the remaining non-dashed arguments. ParseOptions include output_functor(Func), duplicated_flags(Keep) (one of keepfirst, keeplast, keepall; default keeplast), and allow_empty_flag_spec(Bool) (default true).

Compilation flags:

static

Template:

parse(OptionObjects,AppArguments,Options,PositionalArguments,ParseOptions)

Mode and number of proofs:

parse(+list(object),+list(atom),-list,-list(atom),+list) - one_or_error

Exceptions:

ParseOptions is a variable, a partial list, or contains a variable option:

instantiation_error

ParseOptions is neither a variable nor a list:

type_error(list,ParseOptions)

An element of ParseOptions is neither a variable nor a compound term:

type_error(compound,Option)

An element of ParseOptions is a compound term but not a valid option:

domain_error(option,Option)

OptionObjects is a variable, a partial list, or contains an option object definition with an insufficiently instantiated value:

instantiation_error

OptionObjects is neither a variable nor a list of valid object identifiers:

type_error(list(object),OptionObjects)

An option object is missing the name/1 predicate:

existence_error(predicate,name/1)

An option object predicate returns a value with an invalid type:

type_error(Type,Term)

An option object predicate returns a value outside the expected domain:

domain_error(Domain,Term)

The option set contains a duplicate option name:

domain_error(unique_key,Name)

The option set contains a duplicate short flag:

domain_error(unique_short_flag,ShortFlag)

The option set contains a duplicate long flag:

domain_error(unique_long_flag,LongFlag)

An option has no short or long flags and empty flag specifications are disallowed:

domain_error(non_empty_flag_spec,Name)

AppArguments is a variable or a partial list:

instantiation_error

AppArguments is neither a variable nor a list of atoms:

type_error(list(atom),AppArguments)

An unknown flag is found:

existence_error(command_line_option,Argument)

A flag value cannot be parsed as the option type:

type_error(flag_value,Type)

A short option is written using the disallowed -f=value syntax:

syntax_error(disallowed: <shortflag>=<value>)

---

help/2

Synthesizes a help text Help as an atom from the option objects OptionObjects using default help options.

Compilation flags:

static

Template:

help(OptionObjects,Help)

Mode and number of proofs:

help(+list(object),-atom) - one_or_error

Exceptions:

OptionObjects is a variable, a partial list, or contains an option object definition with an insufficiently instantiated value:

instantiation_error

OptionObjects is neither a variable nor a list of valid object identifiers:

type_error(list(object),OptionObjects)

An option object is missing the name/1 predicate:

existence_error(predicate,name/1)

An option object predicate returns a value with an invalid type:

type_error(Type,Term)

An option object predicate returns a value outside the expected domain:

domain_error(Domain,Term)

The option set contains a duplicate option name:

domain_error(unique_key,Name)

The option set contains a duplicate short flag:

domain_error(unique_short_flag,ShortFlag)

The option set contains a duplicate long flag:

domain_error(unique_long_flag,LongFlag)

---

help/3

Synthesizes a help text Help as an atom from the option objects OptionObjects using the given HelpOptions. HelpOptions include line_width(Width) (default 80), min_help_width(Width) (default 40), break_long_flags(Boolean) (default false), suppress_empty_meta(Boolean) (default true), and allow_empty_flag_spec(Bool) (default true).

Compilation flags:

static

Template:

help(OptionObjects,Help,HelpOptions)

Mode and number of proofs:

help(+list(object),-atom,+list) - one_or_error

Exceptions:

HelpOptions is a variable, a partial list, or contains a variable option:

instantiation_error

HelpOptions is neither a variable nor a list:

type_error(list,HelpOptions)

An element of HelpOptions is neither a variable nor a compound term:

type_error(compound,Option)

An element of HelpOptions is a compound term but not a valid option:

domain_error(option,Option)

OptionObjects is a variable, a partial list, or contains an option object definition with an insufficiently instantiated value:

instantiation_error

OptionObjects is neither a variable nor a list of valid object identifiers:

type_error(list(object),OptionObjects)

An option object is missing the name/1 predicate:

existence_error(predicate,name/1)

An option object predicate returns a value with an invalid type:

type_error(Type,Term)

An option object predicate returns a value outside the expected domain:

domain_error(Domain,Term)

The option set contains a duplicate option name:

domain_error(unique_key,Name)

The option set contains a duplicate short flag:

domain_error(unique_short_flag,ShortFlag)

The option set contains a duplicate long flag:

domain_error(unique_long_flag,LongFlag)

An option has no short or long flags and empty flag specifications are disallowed:

domain_error(non_empty_flag_spec,Name)

---

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)

See also

command_line_option