JarCastingexificient-for-javascript
EXI for JavaScript (Explorative) - How EXI can be used to represent JavaScript efficiently w.r.t.
- Size and
- Processing speed
Implementations:
Abstract Syntax Tree (AST) for JavaScript
We re-use the syntax tree format as standardized by EStree project. See also
Sample
JavaScript
var dog = 6, cat = 7, pig = dog * cat;
EXI for JavaScript (visualized as XML)
<Program>
<body>
<array>
<VariableDeclaration>
<declarations>
<array>
<VariableDeclarator>
<id>
<Identifier>
<name>dog</name>
</Identifier>
</id>
<init>
<Literal>
<value>
<integer>6</integer>
</value>
</Literal>
</init>
</VariableDeclarator>
</array>
</declarations>
<kind>var</kind>
</VariableDeclaration>
<VariableDeclaration>
<declarations>
<array>
<VariableDeclarator>
<id>
<Identifier>
<name>cat</name>
</Identifier>
</id>
<init>
<Literal>
<value>
<integer>7</integer>
</value>
</Literal>
</init>
</VariableDeclarator>
</array>
</declarations>
<kind>var</kind>
</VariableDeclaration>
<VariableDeclaration>
<declarations>
<array>
<VariableDeclarator>
<id>
<Identifier>
<name>pig</name>
</Identifier>
</id>
<init>
<BinaryExpression>
<operator>*</operator>
<left>
<Identifier>
<name>dog</name>
</Identifier>
</left>
<right>
<Identifier>
<name>cat</name>
</Identifier>
</right>
</BinaryExpression>
</init>
</VariableDeclarator>
</array>
</declarations>
<kind>var</kind>
</VariableDeclaration>
</array>
</body>
</Program>
Early Results
See test-data in https://github.com/EXIficient/exificient-for-javascript/tree/master/src/test/resources.
Compression
| TestCase | JavaScript [Size in Bytes] | EXI 4 JS [Size in Bytes] |
|---|---|---|
| angular2.js | 1182582 | 388994 |
| angular2.min.js | 635809 | 375410 |
| animals.js | 40 | 30 |
| browserDetection.js | 885 | 316 |
| jquery.js | 263767 | 72755 |
| jquery.min.js | 86355 | 58250 |
| react.js | 701412 | 200306 |
| react.min.js | 148805 | 101384 |
| xCryptic.app.js | 5611 | 2508 |
On average "EXI for JS" is about 50% of the original JavaScript filesize!
