Meta-Language Parser

A recursive descent parser for the IceProd meta language. Most commonly used in IceProd dataset configurations to refer to other parts of the same configuration.

class iceprod.core.parser.ExpParser

Expression parsing class for parameter values.

Grammar Definition:

char     := any unicode character other than $()[]
word     := char | char + word
starter  := $
scopeL   := (
scopeR   := )
bracketL := [
bracketR := ]
symbol   := starter | starter + word
phrase   := symbol + scopeL + sentence + scopeR
lookup   := word + bracketL + word + bracketR | phrase + bracketL + word + bracketR
sentence := lookup | phrase | word | lookup + sentence | phrase + sentence | word + sentence

Keywords:

• steering : A parameter from iceprod.core.dataclasses.Steering

• system : A system value from iceprod.core.dataclasses.Steering

• args, options : An option value from iceprod.core.dataclasses.Job

• metadata : A value from iceprod.core.dataclasses.Dif or iceprod.core.dataclasses.Plus

• eval : An arithmatic expression

• sum, min, max, len : Apply a reduction to a sequence

• choice : A random choice from a list of possibilites

• sprintf : The sprintf string syntax

Examples:

$steering(my_parameter)
$system(gpu_opts)
$args(option1)
$options(option1)
$metadata(sensor_name)
$eval(1+2)
$choice(1,2,3,4)
$sprintf("%04d",4)

parse(input, job=None, env=None, depth=20)

Parse the input, expanding where possible.

Parameters:

• input – input string

• job – iceprod.core.dataclasses.Job, optional

• env – env dictionary, optional

• depth – how deep to recursively parse

Returns:

expanded string

classmethod safe_eval.eval(expr)

Safe evaluation of arithmatic operations using Abstract Syntax Trees.