This file contains the common helper functions that we'd like to share among the Lexer, Rewriter, and the Nodes. Merge objects, flatten arrays, count characters, that sort of thing.
Peek at the beginning of a given string to see if it matches a sequence.
exports.starts = (string, literal, start) -> literal is string.substr start, literal.length
Peek at the end of a given string to see if it matches a sequence.
exports.ends = (string, literal, back) -> len = literal.length literal is string.substr string.length - len - (back or 0), len
Repeat a string n times.
exports.repeat = repeat = (str, n) ->Use clever algorithm to have O(log(n)) string concatenation operations.
res = '' while n > 0 res += str if n & 1 n >>>= 1 str += str res
Trim out all falsy values from an array.
exports.compact = (array) -> item for item in array when item
Count the number of occurrences of a string in a string.
exports.count = (string, substr) -> num = pos = 0 return 1/0 unless substr.length num++ while pos = 1 + string.indexOf substr, pos num
Merge objects, returning a fresh copy with attributes from both sides.
Used every time Base#compile is called, to allow properties in the
options hash to propagate down the tree without polluting other branches.
exports.merge = (options, overrides) ->
extend (extend {}, options), overridesExtend a source object with the properties of another object (shallow copy).
extend = exports.extend = (object, properties) -> for key, val of properties object[key] = val object
Return a flattened version of an array.
Handy for getting a list of children from the nodes.
exports.flatten = flatten = (array) -> flattened = [] for element in array if element instanceof Array flattened = flattened.concat flatten element else flattened.push element flattened
Delete a key from an object, returning the value. Useful when a node is looking for a particular method in an options hash.
exports.del = (obj, key) -> val = obj[key] delete obj[key] val
Gets the last item of an array(-like) object.
exports.last = last = (array, back) -> array[array.length - (back or 0) - 1]
Typical Array::some
exports.some = Array::some ? (fn) -> return true for e in this when fn e false
Simple function for inverting Literate CoffeeScript code by putting the documentation in comments, producing a string of CoffeeScript code that can be compiled "normally".
exports.invertLiterate = (code) -> maybe_code = true lines = for line in code.split('\n') if maybe_code and /^([ ]{4}|[ ]{0,3}\t)/.test line line else if maybe_code = /^\s*$/.test line line else '# ' + line lines.join '\n'
Merge two jison-style location data objects together.
If last is not provided, this will simply return first.
buildLocationData = (first, last) -> if not last first else first_line: first.first_line first_column: first.first_column last_line: last.last_line last_column: last.last_column
This returns a function which takes an object as a parameter, and if that object is an AST node, updates that object's locationData. The object is returned either way.
exports.addLocationDataFn = (first, last) -> (obj) -> if ((typeof obj) is 'object') and (!!obj['updateLocationDataIfMissing']) obj.updateLocationDataIfMissing buildLocationData(first, last) return obj
Convert jison location data to a string.
obj can be a token, or a locationData.
exports.locationDataToString = (obj) -> if ("2" of obj) and ("first_line" of obj[2]) then locationData = obj[2] else if "first_line" of obj then locationData = obj if locationData "#{locationData.first_line + 1}:#{locationData.first_column + 1}-" + "#{locationData.last_line + 1}:#{locationData.last_column + 1}" else "No location data"
A .coffee.md compatible version of basename, that returns the file sans-extension.
exports.baseFileName = (file, stripExt = no, useWinPathSep = no) -> pathSep = if useWinPathSep then /\\|\// else /\// parts = file.split(pathSep) file = parts[parts.length - 1] return file unless stripExt parts = file.split('.') parts.pop() parts.pop() if parts[parts.length - 1] is 'coffee' and parts.length > 1 parts.join('.')
Determine if a filename represents a (Iced)?CoffeeScript file.
exports.isCoffee = (file) -> /\.((lit)?coffee|coffee\.md|iced)$/.test file
Determine if a filename represents a Literate CoffeeScript file.
exports.isLiterate = (file) -> /\.(litcoffee|coffee\.md)$/.test file
Throws a SyntaxError with a source file location data attached to it in a
property called location.
exports.throwSyntaxError = (message, location) -> location.last_line ?= location.first_line location.last_column ?= location.first_column error = new SyntaxError message error.location = location throw error
Creates a nice error message like, following the "standard" format
exports.prettyErrorMessage = (error, filename, code, useColors) -> return error.stack or "#{error}" unless error.location
Prefer original source file information stored in the error if present.
filename = error.filename or filename code = error.code or code {first_line, first_column, last_line, last_column} = error.location codeLine = code.split('\n')[first_line] start = first_column
Show only the first line on multi-line errors.
end = if first_line is last_line then last_column + 1 else codeLine.length marker = repeat(' ', start) + repeat('^', end - start) if useColors colorize = (str) -> "\x1B[1;31m#{str}\x1B[0m" codeLine = codeLine[...start] + colorize(codeLine[start...end]) + codeLine[end..] marker = colorize marker message = """ #{filename}:#{first_line + 1}:#{first_column + 1}: error: #{error.message} #{codeLine} #{marker} """
Uncomment to add stacktrace. message += "\n#{error.stack}"
message