The minifier is based on the semantics of jsmin.c by Douglas Crockford.
Copyright 2011 - 2019 André Malo or his licensors, as applicable
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The module is a re-implementation aiming for speed, so it can be used at
runtime (rather than during a preprocessing step). Usually it produces the
same results as the original
jsmin.c. It differs in the following ways:
Control characters inside string and regex literals are left untouched; they are not converted to spaces (nor to n)
Newline characters are not allowed inside string and regex literals, except for line continuations in string literals (ECMA-5).
“return /regex/” is recognized correctly.
More characters are allowed before regexes.
Line terminators after regex literals are handled more sensibly
“+ +” and “- -” sequences are not collapsed to ‘++’ or ‘–’
Newlines before ! operators are removed more sensibly
(Unnested) template literals are supported (ECMA-6)
Comments starting with an exclamation mark (
!) can be kept optionally
rJSmin does not handle streams, but only complete strings. (However, the module provides a “streamy” interface).
Since most parts of the logic are handled by the regex engine it’s way faster
than the original python port of
jsmin.c by Baruch Even. The speed factor
varies between about 6 and 55 depending on input and python version (it gets
faster the more compressed the input already is). Compared to the
speed-refactored python port by Dave St.Germain the performance gain is less
dramatic but still between 3 and 50 (for huge inputs). See the docs/BENCHMARKS
file for details.
rjsmin.c is a reimplementation of rjsmin.py in C and speeds it up even more.
Supported python versions are 2.7 and 3.4+.
Instead of parsing the stream char by char, it uses a regular expression approach which minifies the whole script with one big substitution regex.
This is a hand crafted C implementation built on the regex semantics.
Script to minify
Keep comments starting with an exclamation mark? (