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Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 57 |
1 files changed, 51 insertions, 6 deletions
@@ -300,7 +300,6 @@ Acorn is really fast (e.g. 250ms instead of 380ms on some 650K code), but converting the SpiderMonkey tree that Acorn produces takes another 150ms so in total it's a bit more than just using UglifyJS's own parser. - API Reference ------------- @@ -313,7 +312,53 @@ It exports a lot of names, but I'll discuss here the basics that are needed for parsing, mangling and compressing a piece of code. The sequence is (1) parse, (2) compress, (3) mangle, (4) generate output code. -### The parser +### The simple way + +There's a single toplevel function which combines all the steps. If you +don't need additional customization, you might want to go with `minify`. +Example: + + var result = UglifyJS.minify("/path/to/file.js"); + console.log(result.code); // minified output + +You can also compress multiple files: + + var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ]); + console.log(result.code); + +To generate a source map: + + var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ], { + outSourceMap: "out.js.map" + }); + console.log(result.code); // minified output + console.log(result.map); + +Note that the source map is not saved in a file, it's just returned in +`result.map`. The value passed for `outSourceMap` is only used to set the +`file` attribute in the source map (see [the spec][sm-spec]). + +If you're compressing compiled JavaScript and have a source map for it, you +can use the `inSourceMap` argument: + + var result = UglifyJS.minify("compiled.js", { + inSourceMap: "compiled.js.map", + outSourceMap: "minified.js.map" + }); + // same as before, it returns `code` and `map` + +The `inSourceMap` is only used if you also request `outSourceMap` (it makes +no sense otherwise). + +We could add more options to `UglifyJS.minify` — if you need additional +functionality please suggest! + +### The hard way + +Following there's more detailed API info, in case the `minify` function is +too simple for your needs. + +#### The parser var toplevel_ast = UglifyJS.parse(code, options); @@ -342,7 +387,7 @@ something like this: After this, we have in `toplevel` a big AST containing all our files, with each token having proper information about where it came from. -### Scope information +#### Scope information UglifyJS contains a scope analyzer that you need to call manually before compressing or mangling. Basically it augments various nodes in the AST @@ -354,7 +399,7 @@ anything with the tree: toplevel.figure_out_scope() -### Compression +#### Compression Like this: @@ -368,7 +413,7 @@ scripts. The compressor is destructive, so don't rely that `toplevel` remains the original tree. -### Mangling +#### Mangling After compression it is a good idea to call again `figure_out_scope` (since the compressor might drop unused variables / unreachable code and this might @@ -380,7 +425,7 @@ non-mangleable words). Example: compressed_ast.compute_char_frequency(); compressed_ast.mangle_names(); -### Generating output +#### Generating output AST nodes have a `print` method that takes an output stream. Essentially, to generate code you do this: |