56 lines
755 B
Markdown
56 lines
755 B
Markdown
# Syntax Analysis
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## Context-Free Grammars (CFG)
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## Parse Tree
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A tree representation of the derivation
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parse tree has `terminals` at the leaves, `non-terminals` at the interior.
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An in-order traversal of the leaves is the original input.
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* leftmost derivation
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* rightmost derivation
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### Ambiguity
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should be removed
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for example: `A + B * C` should be resolved
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**removing ambiguity**
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### AST (Abstract Syntax Tree)
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### Error Handling
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One of the purposes of the compiler is error handling.
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- to detect non-valid programs
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- and to translate the non-valid to the valid
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## Parsing
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* Top-down Parsing
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**Recursive Descent Parsing**
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by using backtracking
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* Predictive Parsing
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Parsing Table: no need to backtrack.
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### Parser Implement
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