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Mihai Bazon
2015-03-29 13:13:40 +03:00
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@@ -52,70 +52,87 @@ a double dash to prevent input files being used as option arguments:
The available options are: The available options are:
``` ```
--source-map Specify an output file where to generate source map. --source-map Specify an output file where to generate source
[string] map.
--source-map-root The path to the original source to be included in the --source-map-root The path to the original source to be included
source map. [string] in the source map.
--source-map-url The path to the source map to be added in //# --source-map-url The path to the source map to be added in //#
sourceMappingURL. Defaults to the value passed with sourceMappingURL. Defaults to the value passed
--source-map. [string] with --source-map.
--source-map-include-sources --source-map-include-sources Pass this flag if you want to include the
Pass this flag if you want to include the content of content of source files in the source map as
source files in the source map as sourcesContent sourcesContent property.
property. [boolean] --in-source-map Input source map, useful if you're compressing
--in-source-map Input source map, useful if you're compressing JS that was JS that was generated from some other original
generated from some other original code. code.
--screw-ie8 Pass this flag if you don't care about full compliance --screw-ie8 Pass this flag if you don't care about full
with Internet Explorer 6-8 quirks (by default UglifyJS compliance with Internet Explorer 6-8 quirks
will try to be IE-proof). [boolean] (by default UglifyJS will try to be IE-proof).
--expr Parse a single expression, rather than a program (for --expr Parse a single expression, rather than a
parsing JSON) [boolean] program (for parsing JSON)
-p, --prefix Skip prefix for original filenames that appear in source -p, --prefix Skip prefix for original filenames that appear
maps. For example -p 3 will drop 3 directories from file in source maps. For example -p 3 will drop 3
names and ensure they are relative paths. You can also directories from file names and ensure they are
specify -p relative, which will make UglifyJS figure out relative paths. You can also specify -p
itself the relative paths between original sources, the relative, which will make UglifyJS figure out
source map and the output file. [string] itself the relative paths between original
sources, the source map and the output file.
-o, --output Output file (default STDOUT). -o, --output Output file (default STDOUT).
-b, --beautify Beautify output/specify output options. [string] -b, --beautify Beautify output/specify output options.
-m, --mangle Mangle names/pass mangler options. [string] -m, --mangle Mangle names/pass mangler options.
-r, --reserved Reserved names to exclude from mangling. -r, --reserved Reserved names to exclude from mangling.
-c, --compress Enable compressor/pass compressor options. Pass options -c, --compress Enable compressor/pass compressor options. Pass
like -c hoist_vars=false,if_return=false. Use -c with no options like -c
argument to use the default compression options. [string] hoist_vars=false,if_return=false. Use -c with
-d, --define Global definitions [string] no argument to use the default compression
-e, --enclose Embed everything in a big function, with a configurable options.
parameter/argument list. [string] -d, --define Global definitions
--comments Preserve copyright comments in the output. By default this -e, --enclose Embed everything in a big function, with a
works like Google Closure, keeping JSDoc-style comments configurable parameter/argument list.
that contain "@license" or "@preserve". You can optionally --comments Preserve copyright comments in the output. By
pass one of the following arguments to this flag: default this works like Google Closure, keeping
JSDoc-style comments that contain "@license" or
"@preserve". You can optionally pass one of the
following arguments to this flag:
- "all" to keep all comments - "all" to keep all comments
- a valid JS regexp (needs to start with a slash) to keep - a valid JS regexp (needs to start with a
only comments that match. slash) to keep only comments that match.
Note that currently not *all* comments can be kept when Note that currently not *all* comments can be
compression is on, because of dead code removal or kept when compression is on, because of dead
cascading statements into sequences. [string] code removal or cascading statements into
--preamble Preamble to prepend to the output. You can use this to sequences.
insert a comment, for example for licensing information. --preamble Preamble to prepend to the output. You can use
This will not be parsed, but the source map will adjust this to insert a comment, for example for
for its presence. licensing information. This will not be
--stats Display operations run time on STDERR. [boolean] parsed, but the source map will adjust for its
--acorn Use Acorn for parsing. [boolean] presence.
--spidermonkey Assume input files are SpiderMonkey AST format (as JSON). --stats Display operations run time on STDERR.
[boolean] --acorn Use Acorn for parsing.
--spidermonkey Assume input files are SpiderMonkey AST format
(as JSON).
--self Build itself (UglifyJS2) as a library (implies --self Build itself (UglifyJS2) as a library (implies
--wrap=UglifyJS --export-all) [boolean] --wrap=UglifyJS --export-all)
--wrap Embed everything in a big function, making the “exports” --wrap Embed everything in a big function, making the
and “global” variables available. You need to pass an “exports” and “global” variables available. You
argument to this option to specify the name that your need to pass an argument to this option to
module will take when included in, say, a browser. specify the name that your module will take
[string] when included in, say, a browser.
--export-all Only used when --wrap, this tells UglifyJS to add code to --export-all Only used when --wrap, this tells UglifyJS to
automatically export all globals. [boolean] add code to automatically export all globals.
--lint Display some scope warnings [boolean] --lint Display some scope warnings
-v, --verbose Verbose [boolean] -v, --verbose Verbose
-V, --version Print version number and exit. [boolean] -V, --version Print version number and exit.
--noerr Don't throw an error for unknown options in -c,
-b or -m.
--bare-returns Allow return outside of functions. Useful when
minifying CommonJS modules.
--keep-fnames Do not mangle/drop function names. Useful for
code relying on Function.prototype.name.
--reserved-file File containing reserved names
--reserve-domprops Make (most?) DOM properties reserved for
--mangle-props
--mangle-props Mangle property names
--name-cache File to hold mangled names mappings
``` ```
Specify `--output` (`-o`) to declare the output file. Otherwise the output Specify `--output` (`-o`) to declare the output file. Otherwise the output
@@ -189,6 +206,69 @@ comma-separated list of names. For example:
to prevent the `require`, `exports` and `$` names from being changed. to prevent the `require`, `exports` and `$` names from being changed.
### Mangling property names (`--mangle-props`)
**Note:** this will probably break your code. Mangling property names is a
separate step, different from variable name mangling. Pass
`--mangle-props`. It will mangle all properties that are seen in some
object literal, or that are assigned to. For example:
```js
var x = {
foo: 1
};
x.bar = 2;
x["baz"] = 3;
x[condition ? "moo" : "boo"] = 4;
console.log(x.something());
```
In the above code, `foo`, `bar`, `baz`, `moo` and `boo` will be replaced
with single characters, while `something()` will be left as is.
In order for this to be of any use, we should avoid mangling standard JS
names. For instance, if your code would contain `x.length = 10`, then
`length` becomes a candidate for mangling and it will be mangled throughout
the code, regardless if it's being used as part of your own objects or
accessing an array's length. To avoid that, you can use `--reserved-file`
to pass a filename that should contain the names to be excluded from
mangling. This file can be used both for excluding variable names and
property names. It could look like this, for example:
```js
{
"vars": [ "define", "require", ... ],
"props": [ "length", "prototype", ... ]
}
```
`--reserved-file` can be an array of file names (either a single
comma-separated argument, or you can pass multiple `--reserved-file`
arguments) — in this case it will exclude names from all those files.
A default exclusion file is provided in `tools/domprops.json` which should
cover most standard JS and DOM properties defined in various browsers. Pass
`--reserve-domprops` to read that in.
When you compress multiple files using this option, in order for them to
work together in the end we need to ensure somehow that one property gets
mangled to the same name in all of them. For this, pass `--name-cache
filename.json` and UglifyJS will maintain these mappings in a file which can
then be reused. It should be initially empty. Example:
```
rm -f /tmp/cache.json # start fresh
uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js
```
Now, `part1.js` and `part2.js` will be consistent with each other in terms
of mangled property names.
Using the name cache is not necessary if you compress all your files in a
single call to UglifyJS.
## Compressor options ## Compressor options
You need to pass `--compress` (`-c`) to enable the compressor. Optionally You need to pass `--compress` (`-c`) to enable the compressor. Optionally