1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
.. SlimIt documentation master file, created by
sphinx-quickstart on Mon May 2 11:51:24 2011.
You can adapt this file completely to your liking, but it should at least
contain the root `toctree` directive.
Welcome to SlimIt
==================================
`SlimIt` is a JavaScript minifier written in Python.
It compiles JavaScript into more compact code so that it downloads
and runs faster.
`SlimIt` also provides a library that includes a JavaScript parser,
lexer, pretty printer and a tree visitor.
`http://slimit.org/ <http://slimit.org/>`_
Installation
------------
.. code-block:: bash
$ [sudo] pip install slimit
Or the bleeding edge version from the git master branch:
.. code-block:: bash
$ [sudo] pip install git+https://github.com/rspivak/slimit.git#egg=slimit
Let's minify some code
----------------------
From the command line:
.. code-block:: bash
$ slimit -h
Usage: slimit [options] [input file]
If no input file is provided STDIN is used by default.
Minified JavaScript code is printed to STDOUT.
Options:
-h, --help show this help message and exit
-m, --mangle mangle names
-t, --mangle-toplevel
mangle top level scope (defaults to False)
$ cat test.js
var foo = function( obj ) {
for ( var name in obj ) {
return false;
}
return true;
};
$
$ slimit --mangle < test.js
var foo=function(a){for(var b in a)return false;return true;};
Or using library API:
.. code-block:: python
>>> from slimit import minify
>>> text = """
... var a = function( obj ) {
... for ( var name in obj ) {
... return false;
... }
... return true;
... };
... """
>>> print minify(text, mangle=True, mangle_toplevel=True)
var a=function(a){for(var b in a)return false;return true;};
Iterate over, modify a JavaScript AST and pretty print it
---------------------------------------------------------
>>> from slimit.parser import Parser
>>> from slimit.visitors import nodevisitor
>>> from slimit import ast
>>>
>>> parser = Parser()
>>> tree = parser.parse('for(var i=0; i<10; i++) {var x=5+i;}')
>>> for node in nodevisitor.visit(tree):
... if isinstance(node, ast.Identifier) and node.value == 'i':
... node.value = 'hello'
...
>>> print tree.to_ecma() # print awesome javascript :)
for (var hello = 0; hello < 10; hello++) {
var x = 5 + hello;
}
>>>
Writing custom node visitor
---------------------------
>>> from slimit.parser import Parser
>>> from slimit.visitors.nodevisitor import ASTVisitor
>>>
>>> text = """
... var x = {
... "key1": "value1",
... "key2": "value2"
... };
... """
>>>
>>> class MyVisitor(ASTVisitor):
... def visit_Object(self, node):
... """Visit object literal."""
... for prop in node:
... left, right = prop.left, prop.right
... print 'Property key=%s, value=%s' % (left.value, right.value)
... # visit all children in turn
... self.visit(prop)
...
>>>
>>> parser = Parser()
>>> tree = parser.parse(text)
>>> visitor = MyVisitor()
>>> visitor.visit(tree)
Property key="key1", value="value1"
Property key="key2", value="value2"
Using lexer in your project
---------------------------
>>> from slimit.lexer import Lexer
>>> lexer = Lexer()
>>> lexer.input('a = 1;')
>>> for token in lexer:
... print token
...
LexToken(ID,'a',1,0)
LexToken(EQ,'=',1,2)
LexToken(NUMBER,'1',1,4)
LexToken(SEMI,';',1,5)
You can get one token at a time using ``token`` method:
>>> lexer.input('a = 1;')
>>> while True:
... token = lexer.token()
... if not token:
... break
... print token
...
LexToken(ID,'a',1,0)
LexToken(EQ,'=',1,2)
LexToken(NUMBER,'1',1,4)
LexToken(SEMI,';',1,5)
`LexToken` instance has different attributes:
>>> lexer.input('a = 1;')
>>> token = lexer.token()
>>> token.type, token.value, token.lineno, token.lexpos
('ID', 'a', 1, 0)
Benchmarks
----------
**SAM** - JQuery size after minification in bytes
+-------------------------------+------------+------------+------------+
| Original jQuery 1.6.1 (bytes) | SlimIt SAM | rJSmin SAM | jsmin SAM |
+===============================+============+============+============+
| 234,995 | 94,290 | 134,215 | 134,819 |
+-------------------------------+------------+------------+------------+
Roadmap
-------
- More minifications
- Speed improvements
.. toctree::
:maxdepth: 2
License
-------
The MIT License (MIT)
|
