CODEWITHSUNDEEP
grammarxtext
clericc
clericc

Reputation: 305

Xtext: Boolean feature consuming a token series

as you know, it is possible to make a boolean feature like

tokenExist ?= 'TOKEN'?

How can i know consume more than one token like this:

tokensExist ?= ('TOKENONE' 'TOKENTWO')?

This is not valid in Xtext.

My current solution approach looks like this:

(tokensExist ?='TOKENONE' 'TOKENTWO')?

works, but does not really express what is meant

Any ideas?

Upvotes: 1

Views: 520

Answers (1)

Boris Brodski
Boris Brodski

Reputation: 8715

Your approach is ok. You save the presence of the first (or any other) token in the sequence to the tokensExist boolean field. The presence and order of the other tokens are guaranteed by the parser.

Upvotes: 1

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