Until Combinator

[sinclairzx81]

This PR adds a new combinator called Until

This combinator will parse any character up until the specified sentinel is reached. As per documentation.

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Until

The Until combinator parses all characters up to (but not including) the specified string. The specified string remains unconsumed in the input. If the string is not found, parsing fails.

BNF

<T> ::= ? any character until 'Z' ?

TypeScript

const T = Runtime.Until('Z')                        // const T = {
                                                    //   type: 'Until',
                                                    //   value: 'X'
                                                    // }

const R = Runtime.Parse(T, 'X Y Z')                 // const R = ['X Y ', 'Z']

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This combinator services the immediate requirement of being able to parse embedded strings (TemplateLiteral syntax) but could replace the current String combinator in subsequent revisions.