ECMAScript parsing infrastructure for multipurpose analysis
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Esprima (, BSD license) is a high performance, standard-compliant ECMAScript parser officially written in ECMAScript (also popularly known as JavaScript) and ported to Python. Esprima is created and maintained by Ariya Hidayat, with the help of many contributors.

Python port is a line-by-line manual translation and was created and is maintained by German Mendez Bravo (Kronuz).



pip install esprima


Esprima can be used to perform lexical analysis (tokenization) or syntactic analysis (parsing) of a JavaScript program.

A simple example:

>>> import esprima
>>> program = 'const answer = 42'

>>> esprima.tokenize(program)
    type: "Keyword",
    value: "const"
}, {
    type: "Identifier",
    value: "answer"
}, {
    type: "Punctuator",
    value: "="
}, {
    type: "Numeric",
    value: "42"

>>> esprima.parseScript(program)
    body: [
            kind: "const",
            declarations: [
                    init: {
                        raw: "42",
                        type: "Literal",
                        value: 42
                    type: "VariableDeclarator",
                    id: {
                        type: "Identifier",
                        name: "answer"
            type: "VariableDeclaration"
    type: "Program",
    sourceType: "script"

For more information, please read the complete documentation.