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What are the basics of PARSE?

April 26, 2017basics parse

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What are the basics of PARSE?

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Here are a few helpful notes on PARSE. 1. PARSE uses it’s own dialect, which in REBOL lingo means that it can have its own grammar and vocabulary. So, don’t make any assumptions about any words that you see in a PARSE block because they live in a separate context and work differently. The great power and leverage of PARSE comes from this very fact, and that’s why dialects are the future. 2. Basic elements are: [block] – a sub-rule to PARSE “string” – attempt to match the string to the input #”c” – attempt to match a single character to the input – match tag to the input (paren) – evaluate a REBOL expression 12 – repeat the pattern 12 times 1 12 – repeat pattern at least 1 but no more than 12. word – look-up word in REBOL, it can be a number, string, block, and PARSE will recognize it. HOWEVER, PARSE also has keywords that are special. word: – mark the current input series position in word :word – set the current input series position from word bitset – match any specified char in