23 lines
451 B
Plaintext
23 lines
451 B
Plaintext
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%include {
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#include <assert.h>
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#include <cstdlib>
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}
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%syntax_error { printf("Lemon syntax error\n"); }
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%token_type {const char*}
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%type expr {float}
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%left PLUS MINUS .
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%extra_argument { float* result }
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start ::= prog.
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prog ::= prog print NL .
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prog ::= prog print .
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prog ::= .
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print ::= expr(a) . { *result = a; }
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expr(a) ::= NUMBER(b) . { a = atof(b); }
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expr(a) ::= expr(b) PLUS expr(c) . { a = b + c; }
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