Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source
Page
Library
Module
Module type
Parameter
Class
Class type
Source
package menhirCST
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source
Page
Library
Module
Module type
Parameter
Class
Class type
Source
Module Make.CSTSource
The module CST offers an algebraic data type cst of concrete syntax trees. This definition is generic, that is, grammar-independent. This module is unsafe: the data constructor NonTerminal has an invariant that is not enforced. A safe, non-generic API can be constructed a posteriori on top of this unsafe, generic API.
The fringe of a CST is a sequence of tokens.
A CST is viable if the parser accepts its fringe and produces the exact same CST again. In general, not every CST is viable: as a typical example, in a grammar of arithmetic expressions where there is a single nonterminal symbol for expressions and where priority declarations are used to resolve shift/reduce conflicts, a CST where an addition node is a child of a multiplication node is not viable. If the grammar is LR(1) then every CST is viable.
A concrete syntax tree (CST) is either a terminal node Terminal tok or a nonterminal node NonTerminal (prod, csts).
A terminal node carries just a token.
A nonterminal node carries a production index prod and an immutable array of subtrees csts. The length of the array csts must be the length of the right-hand side of the production prod. The sequence of the head symbols of the subtrees csts must match the right-hand side of the production prod. The production prod must not be a start production.