esprima {js}

JavaScrip Syntax Tree

Description

Esprima is a high performance, standard-compliant ECMAScript parser. It has full support for ECMAScript 2017 and returns a sensible syntax tree format as standardized by ESTree project.

Usage

esprima_tokenize(text, range = FALSE, loc = FALSE, comment = FALSE)

esprima_parse(text, jsx = FALSE, range = FALSE, loc = FALSE,
  tolerant = FALSE, tokens = FALSE, comment = FALSE)

Arguments

text

a character vector with JavaScript code

range

Annotate each token with its zero-based start and end location

loc

Annotate each token with its column and row-based location

comment

Include every line and block comment in the output

jsx

Support JSX syntax

tolerant

Tolerate a few cases of syntax errors

tokens

Collect every token

Details

The esprima_tokenize function returns a data frame with JavaScript tokens. The esprima_parse function returns the Syntax Tree in JSON format. This can be parsed to R using e.g. jsonlite::fromJSON.

References

Esprima documentation: http://esprima.readthedocs.io/en/4.0/.

Examples

code <- "function test(x, y){ x = x || 1; y = y || 1; return x*y;}"
esprima_tokenize(code)
esprima_parse(code)