ningen 0.4.0

Ninja Build Generation

This package allows a Python script to use file system operations (such as glob) and/or apply any other logic (such as reading structured configuration files) to generate a build.ninja file.

This isn’t intended to replace “high level” build systems such as cmake. Rather, think of it as replacing the clunky GNU make language with Python.

Yes, ninja does provide the ninja_syntax module which already does this. The added value of ningen is:

• Convenience functions for pattern-based build file generation.

• Allow overriding build statements (which complements the pattern-based approach).

Installation

Just pip install ningen (or the equivalent in whatever Python environment you are using).

Usage

The Writer class is similar to the one in ninja_syntax. Two additional utility functions are provided: foreach for iterating on all combinations of several variables, possibly extracting them from existing file names; and expand for generating formatted strings using all the variable combinations.

For example:

import ningen as ng

# Similarly to ninja_syntax writer, but internally buffers everything:
writer = ng.Writer()

modes = ['debug', 'release']
objects = []
writer.rule('compile_debug', ...)
writer.rule('compile_release', ...)

# Ningen provides the "foreach" function,
# which iterates on existing files and/or variable values:
for c in ng.foreach('src/{*name}.cc', mode=modes):
    objects.append(name)
    writer.build(f'obj/{c.mode}/{c.name}.o', f'compile_{c.mode}',
                 inputs=[c.path, ...], ...)

# Since it buffers the data, ningen allows overriding previous build statements:
writer.rule('special_compile_debug', ...)
writer.build('obj/debug/special.o', 'special_compile_gcc',
             inputs=['src/special.cc', ...], ..., override=True)

# Ningen also provides the "expand" function which formats multiple strings:
for mode in modes:
    writer.build('bin/{mode}/program', f'link_{mode}',
                 inputs=ng.expand('obj/{mode}/{object}.o',
                                  mode=mode, object=objects))

# Actually write the buffered ninja build file (by default, to "build.ninja"):
writer.write()