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m WP:CHECKWIKI error fixes + general fixes using AWB (7896) |
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= " if (\e1) \v=\e2; else \v=e3; "
-> " \v=\e1:?\e2:\e3; "
if no_side_effects(
Rewrite '''rule'''s have names, e.g. '''simplify_conditional_assignment'''. Each rule has a ''"match this"'' and ''"replace by that"'' pattern pair separated by '''->''', in our example, on separate lines for readability. The patterns must correspond to language syntax categories; in this case, both patterns must be of syntax category '''statement''' also separated in sympathy with the patterns by '''->'''. Target language (e.g., C) surface syntax is coded inside meta-quotes '''"''', to separate rewrite-rule syntax from that of the target language. Backslashes inside meta-quotes represent ___domain escapes, to indicate pattern meta variables (e.g., '''\v''', '''\e1''', '''\e2''') that match any language construct corresponding to the metavariable declaration in the signature line, e.g., '''e1''' must be of syntactic category: ''(any) expression''. If a metavariable is mentioned multiple times in the ''match'' pattern, it must match to identical subtrees; the same identically shaped '''v''' must occur in both assignments in the match pattern in this example. Metavariables in the ''replace'' pattern are replaced by the corresponding matches from the left side. A conditional clause '''if''' provides an additional condition that must be met for the rule to apply, e.g., that the matched metavariable '''v''', being an arbitrary left-hand side, must not have a side effect (e.g., cannot be of the form of '''a[i++]'''; the '''no_side_effects''' predicate is defined by an analyzer built with other DMS mechanisms).
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