JavaScript-based Python parser. Outputs an abstract syntax tree as specified by the Mozilla Parser API.
This parser is a work in progress, adapted from the JavaScript parser Acorn.
Check out the demo page to see what Filbert can do.
Thank you, we really appreciate you taking the time to help!
Filbert is under active development at https://github.com/differentmatt/filbert. Please submit pull requests or file GitHub issues to that repository. You can also email Matt.
npm install filbert
When run in a CommonJS (node.js) or AMD environment, exported values
appear in the interfaces exposed by the individual files, as usual.
When loaded in the browser without any kind of module management, a
single global object filbert
will be defined, and all the exported
properties will be added to that.
This file contains the actual parser (and is what you get when you
require("filbert")
in node.js).
parse(input, options)
is used to parse a Python program.
The input
parameter is a string, options
can be undefined or an
object setting some of the options listed below. The return value will
be an abstract syntax tree object as specified by the
Mozilla Parser API.
When encountering a syntax error, the parser will raise a
SyntaxError
object with a meaningful message. The error object will
have a pos
property that indicates the character offset at which the
error occurred, and a loc
object that contains a {line, column}
object referring to that same position.
-
locations: When
true
, each node has aloc
object attached withstart
andend
subobjects, each of which contains the one-based line and zero-based column numbers in{line, column}
form. Default isfalse
. -
ranges: To add a semi-standardized "range" property holding a
[start, end]
array with the same numbers, set theranges
option totrue
.
pythonRuntime holds an object required to execute JavaScript code that has been generated from the output AST. (e.g. the builtin len() function is not native to JavaScript). This object must be available if the AST output from parse will be used to generate and execute JavaScript code.
runtimeParamName name of the python runtime object that will be referenced in the output AST. (e.g. if set to '__pythonRuntime', AST nodes will have references to a '__pythonRuntime' object).
tokenize(input, options)
exports a primitive interface to
Filbert's tokenizer. The function takes an input string and options
similar to parse
, and returns a function that can be called repeatedly
to read a single token, and returns a {start, end, type, value}
object
(with added startLoc
and endLoc
properties when the locations
option
is enabled). This object will be reused (updated) for each token, so you
can't count on it staying stable.
tokTypes holds an object mapping names to the token type objects
that end up in the type
properties of tokens.
This file implements an error-tolerant parser. It exposes a single function.
parse_dammit(input, options)
takes the same arguments and
returns the same syntax tree as the parse
function in filbert.js
,
but never raises an error, and will do its best to parse syntactically
invalid code in as meaningful a way as it can. It'll insert identifier
nodes with name "โ"
as placeholders in places where it can't make
sense of the input. Depends on filbert.js
, because it uses the same
tokenizer.
Python3 is the target language. Much of it is working, and the remaining pieces are outlined below.
Keywords:
False None True and break class continue def elif else for if in is not or pass return while
Built-ins:
abs() all() any() ascii() bool() chr() dict() enumerate() filter() float() hex() int() len() list() map() max() min() oct() ord() pow() print() range() repr() reversed() round() sorted() str() sum() tuple()
Keywords:
as assert del except finally from import global lambda nonlocal raise try with yield
Built-ins:
bin() bytearray() bytes() callable() classmethod() compile() complex() delattr() dir() divmod() eval() exec() format() frozenset() getattr() globals() hasattr() hash() help() id() input() isinstance() issubclass() iter() locals() memoryview() next() object() open() property() set() setattr() slice() staticmethod() super() type() vars() zip() _import_()
grunt test
Please use the GitHub issues, or email Matt