parsing - How does an LALR(1) grammar differentiate between a variable and a function call? -

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given following input:

int x = y;

and

int x = y();

is there way lalr(1) grammar avoid shift/reduce conflict? shift/reduce conflict deciding reduce @ y or continue (.

(this assuming variable name can set of alphanumeric characters, , function call set of alphanumeric characters following parentheses.)

it's not shift-reduce conflict unless possible identifier followed ( without being function call. that's not case, although in c-derived languages, there problem of differentiating cast expressions (type)(value) parenthesized-function calls (function)(argument).

if grammar not exhibit particular c wierdness, lalr (1) grammar can decide between shifting , reducing based on (1) token lookahead: if lookahead token (, shifts identifier; otherwise, can reduce.


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