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parse_expression

This library provides a parser for boolean expressions, either represented as an expression with operators &, |, and ~ or as an assignment with operators + or -.

Literal characters and strings are given in single quotes. Parentheses indicate grouping when needed. Square Brackets enclose an optional group of items. Vertical bars separate alternatives. Star indicates that the group should be repeated.

disjunction: conjunction ['|' conjunction ]*
conjunction: complement ['&'  complement ]*
complement: ['~']* (number | variable_name | '(' disjunction ')')
internal_choice: internal_parallel [':' internal_parallel]*
internal_parallel: assignment [',' assignment ]*
assignment: variable_name '+' | variable_name '-' | '(' internal_choice ')'
variable_name: member_name [ '.' member_name ]*
member_name: instance [ slice ]*
slice: '[' number [ '..' number ] ']'

Dependencies:

  • parse
    • common

License

Licensed by Cornell University under GNU GPL v3.

Written by Ned Bingham. Copyright © 2020 Cornell University.

Haystack is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Haystack is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

A copy of the GNU General Public License may be found in COPYRIGHT. Otherwise, see https://www.gnu.org/licenses/.