build-system.jam review et al (fix #562) 💎

[paolopas]

• replaced bjam with b2 in comments
• fixed condition in find-target rule
• removed checking for USER_MODULE in initialize-config-module, that rule was added in 2004 with 2698cc5
• fixed long options big mess 🐞 #562 ^[1], safer and more robust command line argument parsing algorithm implemented in build/build-request.jam, among other changes this also required the moving of various options declarations before the call of the build-request.from-command-line rule, namely --durations, --clean, --clean-all, and --dump-generators
• changed expanded variable in main from global to local
• fixed processing of --durations value, which was ignored, and updated option description to remove default value (not applicable)
• changed .target-times global variable in main to target-times local var
• restored version.build (formerly version.boost-build) rule call, this fixes the --out-xml option
• refined regex in --out-xml processing code
• changed --out-xml target updating algorithm to always use UPDATE_NOW which is available since 2010 with b170b53

et al (b2)

• fixed default value for -j in jam.cpp, the correct value was reported by -v option, which was different that the one reported in the usage by -h
• fixed --keep-going option logic in jam.cpp
• added test/core_cmd_line.py for basic test of command line options processing
• added test/core_option_durations.py for testing of --durations
• added test/core_option_out-xml.py for testing of --out-xml
• updated test/core_fail_expected.py for testing of --keep-going

et al (Lyra)

• removed unused templates/alias is_callable, make_void, valid_t, and basic_token_name
• cleared trailing return type syntax on isContainer, isFlag, setValue, and setFlag methods
• fixed token_iterator::value method
• fixed documentation of bound_parser::choices, typo in main::operator()
• fixed main::operator() method

[1]

In fixing of #562 an important role is played by the update of mod_args with the addiction of has-opt Jam rule (C++ has_opt), this also required the following changes/addictions on Lyra:

• added lyra::has_option function for querying of configured options using same matching criteria (and code) of passed in cli instance
• added forward declaration of class cli, friend declaration of has_option in arguments and cli classes
• added public method bound_parser::is_flag
• changed opt::is_match visibility from protected to public

[paolopas]

pass_d0 here is used only for optimization, it works fine even without

[paolopas]

pass_d0 here is used only for optimization, it works fine even without

[paolopas]

alzheimer