The Perl Toolchain Summit needs more sponsors. If your company depends on Perl, please support this very important event.
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%left '-' '+' 
%left '*' '/' 
%left NEG 
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line:
      %name PROG
      exp <%name EXP + ';' >
;
exp:
      %name NUM
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    | %name VAR
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    | %name PLUS
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    | '(' exp ')' 
;

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