Bottom-up parsing
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Over view of bottom up parsing
Four classes of language commonly used: LR(0) - No lookahead symbol
SLR(1) - Simple with one lookahead symbol
LALR(1) - Lookahead bottom up, not as powerful as full LR(1) but more simple to implement. YACC uses this language
LR(1) - Most general language, but most complex to implement.
Hand coding is very complex for any of these language classes so the use of parser generators is highly recommended.
Parser performs one of two actions (beside accept). These are "Shift" and "Reduce".