Refactor to use ExternalProgram for the command instead of duplicating
that code (badly). Also improve messages to say "or not executable"
when a script/command is not found.
Also allow ExternalPrograms to be passed as arguments to
run_command(). The only thing we're doing by preventing that is
forcing people to use prog.path()
The file will always exist by the time run_command() is invoked, so
there is no reason why we should forbid it. Also allow using File
objects as the command to run since strings are also allowed.
This adds a depdendncy wrapper for llvm-config based on the wxwidgets
dependency. IT handles libs, version, include dir, and the llvm unique
concept of components. These components are individual pieces of the
LLVM library that may or may not be available depending on the platform.
Meson has a common pattern of using 'if len(foo) == 0:' or
'if len(foo) != 0:', however, this is a common anti-pattern in python.
Instead tests for emptiness/non-emptiness should be done with a simple
'if foo:' or 'if not foo:'
Consider the following:
>>> import timeit
>>> timeit.timeit('if len([]) == 0: pass')
0.10730923599840025
>>> timeit.timeit('if not []: pass')
0.030033907998586074
>>> timeit.timeit('if len(['a', 'b', 'c', 'd']) == 0: pass')
0.1154778649979562
>>> timeit.timeit("if not ['a', 'b', 'c', 'd']: pass")
0.08259823200205574
>>> timeit.timeit('if len("") == 0: pass')
0.089759664999292
>>> timeit.timeit('if not "": pass')
0.02340641999762738
>>> timeit.timeit('if len("foo") == 0: pass')
0.08848102600313723
>>> timeit.timeit('if not "foo": pass')
0.04032287199879647
And for the one additional case of 'if len(foo.strip()) == 0', which can
be replaced with 'if not foo.isspace()'
>>> timeit.timeit('if len(" ".strip()) == 0: pass')
0.15294511600222904
>>> timeit.timeit('if " ".isspace(): pass')
0.09413968399894657
>>> timeit.timeit('if len(" abc".strip()) == 0: pass')
0.2023209120015963
>>> timeit.timeit('if " abc".isspace(): pass')
0.09571301700270851
In other words, it's always a win to not use len(), when you don't
actually want to check the length.
Use a titlecase for arbitrary language, this was we don't have 'C' in
lowercase.
Rename 'Static linking library $out' for 'Linking static target $out.'.
Add missing punctuation.
Nirbheek Chauhan
Jussi Pakkanen
Peter Hutterer
Chiu Yue Chun
Dylan Baker
Elliott Sales de Andrade
Guillaume Poirier-Morency
Patrick Griffis
Gabríel Arthúr Pétursson
John Gallagher
Corey Ashford
Ernestas Kulik
Jon Turney
Paolo Borelli
Wade Berrier