Buck: apple_library()
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apple_library()

This is liable to change in the future.

An apple_library() rule represents a set of Objective-C/C++/Swift source files and is similar to a cxx_library() rule with which it shares many attributes. In addition to those common attributes, apple_library() has a some additional attributes that are specific to binaries intended to be built using the Apple toolchain. Note, however, that apple_library() and cxx_library() differ in the way that they import header files, in order to better accommodate existing conventions. See the sections for the headers and exported_headers attributes for more details.

Buck enables you to override components of the Apple toolchain with alternate tools, either from the Xcode search paths or from directories that you specify. See [apple].replacement and [apple].xcode_tool_name_override for more information.

Arguments

  • name (required) #

    The short name for this build target.

  • srcs (defaults to []) #

    The set of C, C++, Objective-C, Objective-C++, or assembly source files to be preprocessed, compiled, and assembled by this rule. We determine which stages to run on each input source based on its file extension. See the GCC documentation for more detail on how file extensions are interpreted. Each element can be either a string specifying a source file (e.g. 'foo/bar.m') or a tuple of a string specifying a source file and a list of compilation flags (e.g. ('foo/bar.m', ['-Wall', '-Werror'])). In the latter case the specified flags will be used in addition to the rule's other flags when preprocessing and compiling that file (if applicable).

  • platform_srcs (defaults to []) #

    Platform specific source files. These should be specified as a list of pairs where the first element is an un-anchored regex (in java.util.regex.Pattern syntax) against which the platform name is matched, and the second element is either a list of source files or a list of tuples of source files and a list of compilation flags to be preprocessed, compiled and assembled if the platform matches the regex. See srcs for more information.

  • headers (defaults to []) #

    The set of header files that are made available for inclusion to the source files in this target. These should be specified as either a list of header files or a dictionary of header names to header files. The header names can contain forward slashes (/). If a list of header files is specified, the headers can be imported with #import "$HEADER_PATH_PREFIX/$HEADER_NAME" or #import "$HEADER_NAME", where $HEADER_PATH_PREFIX is the value of the target's header_path_prefix attribute, and $HEADER_NAME is the filename of the header file. If a dictionary is specified, each header can be imported with #import "$HEADER_NAME", where $HEADER_NAME is the key corresponding to this file. In this case, the header_path_prefix attribute is ignored. In either case, quotes in the import statements can be replaced with angle brackets.

  • exported_headers (defaults to []) #

    The set of header files that are made available for inclusion to the source files in this target and all targets that transitively depend on this one. These should be specified as either a list of header files or a dictionary of header names to header files. The header names can contain forward slashes (/). If a list of header files is specified, the headers can be imported with #import "$HEADER_PATH_PREFIX/$HEADER_NAME" or, if a header file that belongs to the same rule is being imported, with #import "$HEADER_NAME", where $HEADER_PATH_PREFIX is the value of the target's header_path_prefix attribute, and $HEADER_NAME is the filename of the header file. If a dictionary is specified, each header can be imported with #import "$HEADER_NAME", where $HEADER_NAME is the key corresponding to this file. In this case, the header_path_prefix attribute is ignored. In either case, quotes in the import statements can be replaced with angle brackets.

  • header_path_prefix (defaults to name) #

    A path prefix when including headers of this target. For example, headers from a library defined using

    apple_library(
        name = "Library",
        headers = glob(["**/*.h"]),
        header_path_prefix = "Lib",
    )
    
    can be imported using following mapping
    Library/SubDir/Header1.h -> Lib/Header1.h
    Library/Header2.h -> Lib/Header2.h
      
    Defaults to the short name of the target. Can contain forward slashes (/), but cannot start with one. See headers for more information.

  • header_namespace (defaults to name) #

    A path prefix when including headers of this target. Defaults to the path from the root of the repository to the directory where this target is defined. Can contain forward slashes (/), but cannot start with one. See headers for more information.

  • frameworks (defaults to []) #

    A list of system frameworks that the code in this target uses. Each entry should be a path starting with $SDKROOT or $PLATFORM_DIR to denote that the rest of the path is relative to the root of the SDK used for the build or to the platform toolchain directory.

  • preprocessor_flags (defaults to []) #

    Flags to use when preprocessing any of the above sources (which require preprocessing).

  • exported_preprocessor_flags (defaults to []) #

    Just as preprocessor_flags, flags to use when preprocessing any of the above sources (which require preprocessing). However, unlike preprocessor_flags, these preprocessor flags are also used by rules that transitively depend on this rule when preprocessing their own sources.

  • compiler_flags (defaults to []) #

    Flags to use when compiling any of the above sources (which require compilation).

  • platform_compiler_flags (defaults to []) #

    Platform specific compiler flags. These should be specified as a list of pairs where the first element is an un-anchored regex (in java.util.regex.Pattern syntax) against which the platform name is matched, and the second element is a list of flags to use when compiling the target's sources. See compiler_flags for more information.

  • linker_extra_outputs (defaults to []) #

    Declares extra outputs that the linker emits. These identifiers can be used in $(output ...) macros in linker_flags to interpolate the output path into the linker command line. Useful for custom linkers that emit extra output files.

  • linker_flags (defaults to []) #

    Flags to add to the linker command line whenever the output from this rule is used in a link operation, such as linked into an executable or a shared library.

  • exported_linker_flags (defaults to []) #

    Flags to add to the linker command line when the output from this rule, or the output from any rule that transitively depends on this rule, is used in a link operation.

  • exported_platform_linker_flags (defaults to []) #

    Platform-specific linker flags for this rule and for all rules that transitively depend on this rule. This argument is specified as a list of pairs where the first element in each pair is an un-anchored regex against which the platform name is matched. The regex should use java.util.regex.Pattern syntax. The second element in each pair is a list of linker flags. If the regex matches the platform, these flags are added to the linker command line when the output from this rule, or the output from any rule that transitively depends on this rule, is used in a link operation.

  • target_sdk_version (defaults to None) #

    The minimum OS version that the library target should support, overriding the minimum set in.buckconfig. When set, Buck will automatically add flags to both Objective-C and Swift compilation that will allow the use of the new APIs without guarding code inside availability checks.

  • preferred_linkage (defaults to any) #

    Controls how a library should be linked.

    any
    The library will be linked based on its dependents link_style.
    shared
    The library will be always be linked as a shared library.
    static
    The library will be linked as a static library.
    Note: since shared libraries re-export its dependencies, depending on multiple shared libraries which themselves have overlapping static dependencies will cause duplicate symbols.

  • reexport_all_header_dependencies (defaults to True) #

    Whether to automatically re-export the exported headers of all dependencies.

    When this is set to false, only exported headers from exported_deps are re-exported.

  • exported_deps (defaults to []) #

    Dependencies that will also appear to belong to any rules that depend on this one. This has two effects:

    • Exported dependencies will also be included in the link line of dependents of this rules, but normal dependencies will not.
    • When reexport_all_header_dependencies = False, only exported headers of the rules specified here are re-exported.

  • tests (defaults to []) #

    List of build targets that identify the test rules that exercise this target. Note that non apple_test targets will not be included in generated projects due to Xcode's limitations but will still work with buck test.

  • extra_xcode_sources (defaults to []) #

    When the project is generated, this is the list of files that will added to the build phase "Compile Sources" of the given target.

  • extra_xcode_files (defaults to []) #

    When the project is generated, this is the list of files that will added to the project. Those files won't be added to the build phase "Compile Sources".

  • visibility (defaults to []) #

    List of build target patterns that identify the build rules that can include this rule as a dependency, for example, by listing it in their deps or exported_deps attributes. For more information, see visibility.

  • licenses (defaults to []) #

    Set of license files for this library. To get the list of license files for a given build rule and all of its dependencies, you can use buck query.

  • labels (defaults to []) #

    Set of arbitrary strings which allow you to annotate a build rule with tags that can be searched for over an entire dependency tree using buck query attrfilter().

Examples

apple_library(
  name = 'MyLibrary',
  deps = [
    ':OtherLibrary',
    '//Libraries:YetAnotherLibrary',
  ],
  preprocessor_flags = ['-fobjc-arc'],
  headers = [
    'MyHeader.h',
  ],
  srcs = [
    'MySource.m',
    'MySource.swift',
  ],
  frameworks = [
    '$SDKROOT/System/Library/Frameworks/UIKit.framework',
    '$SDKROOT/System/Library/Frameworks/Foundation.framework',
  ],
)