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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:
```
--source-map Specify an output file where to generate source map.
[string]
--source-map-root The path to the original source to be included in the
source map. [string]
--source-map-url The path to the source map to be added in //#
sourceMappingURL. Defaults to the value passed with
--source-map. [string]
--source-map-include-sources
Pass this flag if you want to include the content of
source files in the source map as sourcesContent
property. [boolean]
--in-source-map Input source map, useful if you're compressing JS that was
generated from some other original code.
--screw-ie8 Pass this flag if you don't care about full compliance
with Internet Explorer 6-8 quirks (by default UglifyJS
will try to be IE-proof). [boolean]
--expr Parse a single expression, rather than a program (for
parsing JSON) [boolean]
-p, --prefix Skip prefix for original filenames that appear in source
maps. For example -p 3 will drop 3 directories from file
names and ensure they are relative paths. You can also
specify -p relative, which will make UglifyJS figure out
itself the relative paths between original sources, the
source map and the output file. [string]
-o, --output Output file (default STDOUT).
-b, --beautify Beautify output/specify output options. [string]
-m, --mangle Mangle names/pass mangler options. [string]
-r, --reserved Reserved names to exclude from mangling.
-c, --compress Enable compressor/pass compressor options. Pass options
like -c hoist_vars=false,if_return=false. Use -c with no
argument to use the default compression options. [string]
-d, --define Global definitions [string]
-e, --enclose Embed everything in a big function, with a configurable
parameter/argument list. [string]
--comments Preserve copyright comments in the output. By 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
- a valid JS regexp (needs to start with a slash) to keep
only comments that match.
Note that currently not *all* comments can be kept when
compression is on, because of dead code removal or
cascading statements into sequences. [string]
--preamble Preamble to prepend to the output. You can use this to
insert a comment, for example for licensing information.
This will not be parsed, but the source map will adjust
for its presence.
--stats Display operations run time on STDERR. [boolean]
--acorn Use Acorn for parsing. [boolean]
--spidermonkey Assume input files are SpiderMonkey AST format (as JSON).
[boolean]
--self Build itself (UglifyJS2) as a library (implies
--wrap=UglifyJS --export-all) [boolean]
--wrap Embed everything in a big function, making the “exports”
and “global” variables available. You need to pass an
argument to this option to specify the name that your
module will take when included in, say, a browser.
[string]
--export-all Only used when --wrap, this tells UglifyJS to add code to
automatically export all globals. [boolean]
--lint Display some scope warnings [boolean]
-v, --verbose Verbose [boolean]
-V, --version Print version number and exit. [boolean]
--source-map Specify an output file where to generate source
map.
--source-map-root The path to the original source to be included
in the source map.
--source-map-url The path to the source map to be added in //#
sourceMappingURL. Defaults to the value passed
with --source-map.
--source-map-include-sources Pass this flag if you want to include the
content of source files in the source map as
sourcesContent property.
--in-source-map Input source map, useful if you're compressing
JS that was generated from some other original
code.
--screw-ie8 Pass this flag if you don't care about full
compliance with Internet Explorer 6-8 quirks
(by default UglifyJS will try to be IE-proof).
--expr Parse a single expression, rather than a
program (for parsing JSON)
-p, --prefix Skip prefix for original filenames that appear
in source maps. For example -p 3 will drop 3
directories from file names and ensure they are
relative paths. You can also specify -p
relative, which will make UglifyJS figure out
itself the relative paths between original
sources, the source map and the output file.
-o, --output Output file (default STDOUT).
-b, --beautify Beautify output/specify output options.
-m, --mangle Mangle names/pass mangler options.
-r, --reserved Reserved names to exclude from mangling.
-c, --compress Enable compressor/pass compressor options. Pass
options like -c
hoist_vars=false,if_return=false. Use -c with
no argument to use the default compression
options.
-d, --define Global definitions
-e, --enclose Embed everything in a big function, with a
configurable parameter/argument list.
--comments Preserve copyright comments in the output. By
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
- a valid JS regexp (needs to start with a
slash) to keep only comments that match.
Note that currently not *all* comments can be
kept when compression is on, because of dead
code removal or cascading statements into
sequences.
--preamble Preamble to prepend to the output. You can use
this to insert a comment, for example for
licensing information. This will not be
parsed, but the source map will adjust for its
presence.
--stats Display operations run time on STDERR.
--acorn Use Acorn for parsing.
--spidermonkey Assume input files are SpiderMonkey AST format
(as JSON).
--self Build itself (UglifyJS2) as a library (implies
--wrap=UglifyJS --export-all)
--wrap Embed everything in a big function, making the
“exports” and “global” variables available. You
need to pass an argument to this option to
specify the name that your module will take
when included in, say, a browser.
--export-all Only used when --wrap, this tells UglifyJS to
add code to automatically export all globals.
--lint Display some scope warnings
-v, --verbose Verbose
-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
@@ -189,6 +206,69 @@ comma-separated list of names. For example:
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
You need to pass `--compress` (`-c`) to enable the compressor. Optionally