Dependency object (dep)

Abstract representation of a dependency

Returned by

Dependency object objects are returned by the following functions and methods:

• declare_dependency()
• dependency()
• compiler.find_library()
• dep.as_link_whole()
• dep.as_system()
• dep.partial_dependency()

Dependency object methods

dep.as_link_whole()

Only dependencies created with declare_dependency(), returns a copy of the dependency object with all link_with arguments changed to link_whole. This is useful for example for fallback dependency from a subproject built with default_library=static. Note that all link_with objects must be static libraries otherwise an error will be raised when trying to link_whole a shared library.

dep as_link_whole()

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dep.as_system()

Returns a copy of the dependency object, which has changed the value of include_type to value. The value argument is optional and defaults to 'preserve'.

# Returns a copy of the dependency object, which has changed the value of `include_type`
dep as_system(
  str [value],   # The new value. See dependency() for supported values.
)

Arguments

The method dep.as_system() accepts the following positional arguments:

Name	Type	Description	Tags
value	str	The new value. See dependency() for supported values.	[optional]

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dep.found()

Returns whether the dependency was found.

bool found()

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dep.get_configtool_variable()

Gets the command line argument from the config tool (with -- prepended), or, if invoked on a non config-tool dependency, error out.

# Gets the command line argument from the config tool (with `--` prepended), or,
str get_configtool_variable(
  str var_name,     # Name of the variable to query
)

Arguments

The method dep.get_configtool_variable() accepts the following positional arguments:

Name	Type	Description	Tags
var_name	str	Name of the variable to query

---

dep.get_pkgconfig_variable()

Gets the pkg-config variable specified, or, if invoked on a non pkg-config dependency, error out.

# Gets the pkg-config variable specified,
str get_pkgconfig_variable(
  str var_name,     # Name of the variable to query

  # Keyword arguments:
  default         : str        # The value to return if the variable was not found
  define_variable : list[str]  # You can also redefine a
)

Arguments

The method dep.get_pkgconfig_variable() accepts the following positional arguments:

Name	Type	Description	Tags
var_name	str	Name of the variable to query

Finally, dep.get_pkgconfig_variable() accepts the following keyword arguments:

Name	Type	Description	Tags
default	str	The value to return if the variable was not found. A warning is issued if the variable is not defined and this kwarg is not set.	(since 0.45.0)
define_variable	list[str]	You can also redefine a variable by passing a list to this kwarg that can affect the retrieved variable: ['prefix', '/']). (Since 1.3.0) Multiple variables can be specified in pairs.	(since 0.44.0)

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dep.get_variable()

A generic variable getter method, which replaces the get_*type*_variable methods. This allows one to get the variable from a dependency without knowing specifically how that dependency was found. If default_value is set and the value cannot be gotten from the object then default_value is returned, if it is not set then an error is raised.

# A generic variable getter method, which replaces the
str get_variable(
  str [varname],   # This argument is used as a default value

  # Keyword arguments:
  cmake            : str        # The CMake variable name
  configtool       : str        # The configtool variable name
  default_value    : str        # The default value to return when the variable does not exist
  internal         : str        # The internal variable name
  pkgconfig        : str        # The pkgconfig variable name
  pkgconfig_define : list[str]  # See dep.get_pkgconfig_variable()
)

Arguments

The method dep.get_variable() accepts the following positional arguments:

Name	Type	Description	Tags
varname	str	This argument is used as a default value for cmake, pkgconfig, configtool and internal keyword arguments. It is useful in the common case where pkgconfig and internal use the same variable name, in which case it's easier to write dep.get_variable('foo') instead of dep.get_variable(pkgconfig: 'foo', internal: 'foo').	(since 0.58.0) [optional]

Finally, dep.get_variable() accepts the following keyword arguments:

Name	Type	Description	Tags
cmake	str	The CMake variable name
configtool	str	The configtool variable name
default_value	str	The default value to return when the variable does not exist
internal	str	The internal variable name	(since 0.54.0)
pkgconfig	str	The pkgconfig variable name
pkgconfig_define	list[str]	See dep.get_pkgconfig_variable()

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dep.include_type()

Returns the value set by the include_type kwarg.

str include_type()

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dep.name()

Returns the name of the dependency that was searched. Returns 'internal' for dependencies created with declare_dependency().

NOTE: This was not implemented for dep objects returned by compiler.find_library() until Meson 1.5.0

str name()

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dep.partial_dependency()

Returns a new dependency object with the same name, version, found status, type name, and methods as the object that called it. This new object will only inherit other attributes from its parent as controlled by keyword arguments.

If the parent has any dependencies, those will be applied to the new partial dependency with the same rules. So, given:

dep1 = declare_dependency(compile_args : '-Werror=foo', link_with : 'libfoo')
dep2 = declare_dependency(compile_args : '-Werror=bar', dependencies : dep1)
dep3 = dep2.partial_dependency(compile_args : true)

dep3 will add ['-Werror=foo', '-Werror=bar'] to the compiler args of any target it is added to, but libfoo will not be added to the link_args.

The following arguments will add the following attributes:

• compile_args: any arguments passed to the compiler
• link_args: any arguments passed to the linker
• links: anything passed via link_with or link_whole
• includes: any include_directories
• sources: any compiled or static sources the dependency has

# Returns a new dependency object with the same name, version, found status,
dep partial_dependency(
  compile_args : bool  # Whether to include compile_args
  includes     : bool  # Whether to include includes
  link_args    : bool  # Whether to include link_args
  links        : bool  # Whether to include links
  sources      : bool  # Whether to include sources
)

Arguments

The method dep.partial_dependency() accepts the following keyword arguments:

Name	Type	Description	Tags
compile_args	bool	Whether to include compile_args	default = false
includes	bool	Whether to include includes	default = false
link_args	bool	Whether to include link_args	default = false
links	bool	Whether to include links	default = false
sources	bool	Whether to include sources	default = false

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dep.type_name()

Returns a string describing the type of the dependency, the most common values are internal for deps created with declare_dependency() and pkgconfig for system dependencies obtained with Pkg-config.

str type_name()

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dep.version()

the version number as a string, for example 1.2.8. unknown if the dependency provider doesn't support determining the version.

str version()

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