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diff --git a/docs/CommandLine.rst b/docs/CommandLine.rst index 8a266e23b2..263a025f69 100644 --- a/docs/CommandLine.rst +++ b/docs/CommandLine.rst @@ -1267,6 +1267,57 @@ only consists of one function `cl::ParseCommandLineOptions`_) and three main classes: `cl::opt`_, `cl::list`_, and `cl::alias`_. This section describes these three classes in detail. +.. _cl::getRegisteredOptions: + +The ``cl::getRegisteredOptions`` function +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The ``cl::getRegisteredOptions`` function is designed to give a programmer +access to declared non positional command line options so that how they appear +in ``-help`` can be modified prior to calling `cl::ParseCommandLineOptions`_. +Note this method should not be called during any static initialisation because +it cannot be guaranteed that all options will have been initialised. Hence it +should be called from ``main``. + +This function can be used to gain access to options declared in libraries that +the tool writter may not have direct access to. + +The function retrieves a :ref:`StringMap <dss_stringmap>` that maps the option +string (e.g. ``-help``) to an ``Option*``. + +Here is an example of how the function could be used: + +.. code-block:: c++ + + using namespace llvm; + int main(int argc, char **argv) { + cl::OptionCategory AnotherCategory("Some options"); + + StringMap<cl::Option*> Map; + cl::getRegisteredOptions(Map); + + //Unhide useful option and put it in a different category + assert(Map.count("print-all-options") > 0); + Map["print-all-options"]->setHiddenFlag(cl::NotHidden); + Map["print-all-options"]->setCategory(AnotherCategory); + + //Hide an option we don't want to see + assert(Map.count("enable-no-infs-fp-math") > 0); + Map["enable-no-infs-fp-math"]->setHiddenFlag(cl::Hidden); + + //Change --version to --show-version + assert(Map.count("version") > 0); + Map["version"]->setArgStr("show-version"); + + //Change --help description + assert(Map.count("help") > 0); + Map["help"]->setDescription("Shows help"); + + cl::ParseCommandLineOptions(argc, argv, "This is a small program to demo the LLVM CommandLine API"); + ... + } + + .. _cl::ParseCommandLineOptions: The ``cl::ParseCommandLineOptions`` function |