fastexpr.rs

A fast, tiny, minimal dependency JavaScript expression parser, written in Rust.

Features

• Fast. Hand-coded lexer and top-down operator precedence parser.
• Small. Around ~1000 LOC.
• Compatible. Parses all valid JavaScript expressions. Produces an esprima style AST.

Usage:

let result = parse("(s) => `hello from ${s}!`");match result {Ok(expr) => {println!("{:#?}", expr);}Err(err) => {println!("{:#?}", err);}}

which produces:

ArrowFunction {
params: [
Identifier {
token: Identifier(
"s",
),
},
],
body: TemplateLiteral {
quasis: [
TemplateString {
token: String(
"hello from ",
),
tail: false,
},
TemplateString {
token: String(
"!",
),
tail: true,
},
],
expressions: [
Identifier {
token: Identifier(
"s",
),
},
],
},
}