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|
Nonterminals
root
statement
statements
expr
.
Terminals
int
var
'+'
'-'
'*'
'/'
'='
'('
')'
';;'
.
Rootsymbol
root
.
Right 100 '='.
Left 300 '+'.
Left 300 '-'.
Left 400 '*'.
Left 400 '/'.
Left 600 '('.
root -> statements : '$1'.
statements -> statement : ['$1'].
statements -> statement statements : ['$1'|'$2'].
statements -> statement ';;' statements : ['$1'|'$3'].
statement -> var '=' expr : {assign, '$1', '$3'}.
statement -> expr : {eval, '$1'}.
expr -> int : unwrap('$1').
expr -> var : '$1'.
expr -> expr '+' expr : {add_op, '$1', '$3'}.
expr -> expr '-' expr : {sub_op, '$1', '$3'}.
expr -> expr '*' expr : {mul_op, '$1', '$3'}.
expr -> expr '/' expr : {div_op, '$1', '$3'}.
expr -> '(' expr ')' : '$2'.
Erlang code.
unwrap({int, Line, Value}) -> {int, Line, list_to_integer(Value)}.
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