CS-480/Assignment-2
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Almost finish parser

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This commit is contained in:
Danila Fedorin 2019-05-12 19:01:25 -07:00
parent 51b20b280d
commit 3b2f6baff9
1 changed files with 70 additions and 38 deletions
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108
parser.y
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@ -41,13 +41,37 @@
%token COMMA
%token COLON
%define api.value.type { const char* }
%define api.value.type { std::string* }
%define api.pure full
%define api.push-pull push
%start program
%{
template <typename T, typename std::enable_if<std::is_convertible<T, const char*>::value, T>::type* = nullptr>
void concat(std::string* s, T vs) {
s->append(vs);
}
template <typename T, typename std::enable_if<std::is_convertible<T, std::string*>::value, T>::type* = nullptr>
void concat(std::string* s, T vs) {
s->append(*vs);
delete vs;
}
template <typename T, typename ... Ts>
void concat(std::string* s, T v, Ts ... vs) {
concat(s, v);
concat(s, vs...);
}
template <typename ... Ts>
std::string* concatenate(Ts ... vs) {
std::string* temp = new std::string();
concat(temp, vs...);
return temp;
}
void yyerror(const char* s) {
std::cout << s << std::endl;
}
@ -59,80 +83,88 @@ std::set<std::string> varset;
%%
program
: stmts
: stmts { std::cout << *$1 << std::endl; $$ = $1; }
;
stmts
: stmts stmt
| stmt
: stmts stmt { $$ = concatenate($1, $2); }
| stmt { $$ = $1; }
;
stmt
: expr NEWLINE
| if
| while
| BREAK NEWLINE
: expr NEWLINE { $$ = concatenate($1, ";"); }
| if { $$ = $1; }
| while { $$ = $1; }
| BREAK NEWLINE { $$ = new std::string("break;"); }
;
expr
: assign
| eq
: assign { $$ = $1; }
| eq { $$ = $1; }
;
while
: WHILE expr COLON NEWLINE block
: WHILE expr COLON NEWLINE block { $$ = concatenate("while(", $2, ")", $5); }
;
if
: IF expr COLON NEWLINE block ifend
| IF expr COLON NEWLINE block
: IF expr COLON NEWLINE block elses { $$ = concatenate("if(", $2, ")", $5, $6); }
;
ifend
: ELIF expr COLON NEWLINE block ifend
| ELIF expr COLON NEWLINE block
| ELSE COLON NEWLINE block
elses
: %empty { $$ = new std::string(""); }
| elif elses { $$ = concatenate($1, $2); }
| else { $$ = $1; }
;
elif
: ELIF expr COLON NEWLINE block { $$ = concatenate("else if(", $2, ")", $5); }
;
else
: ELSE COLON NEWLINE block { $$ = concatenate("else", $4); }
;
block
: INDENT stmts DEDENT
: INDENT stmts DEDENT { $$ = concatenate("{", $2, "}"); }
;
assign
: IDENTIFIER ASSIGN expr
: IDENTIFIER ASSIGN expr { varset.insert(*$1); $$ = concatenate($1, "=", $3); }
;
eq
: eq EQ rel
| eq NEQ rel
| rel
: eq EQ rel { $$ = concatenate($1, "==", $3); }
| eq NEQ rel { $$ = concatenate($1, "!=", $3); }
| rel { $$ = $1; }
;
rel
: rel LT sum
| rel LTE sum
| rel GT sum
| rel GTE sum
| sum
: rel LT sum { $$ = concatenate($1, "<", $3); }
| rel LTE sum { $$ = concatenate($1, "<=", $3); }
| rel GT sum { $$ = concatenate($1, ">", $3); }
| rel GTE sum { $$ = concatenate($1, ">=", $3); }
| sum { $$ = $1; }
;
sum
: sum PLUS factor
| sum MINUS factor
| factor
: sum PLUS factor { $$ = concatenate($1, "+", $3); }
| sum MINUS factor { $$ = concatenate($1, "-", $3); }
| factor { $$ = $1; }
;
factor
: factor TIMES term
| factor DIVIDEDBY term
| term
: factor TIMES term { $$ = concatenate($1, "*", $3); }
| factor DIVIDEDBY term { $$ = concatenate($1, "/", $3); }
| term { $$ = $1; }
;
term
: IDENTIFIER
| FLOAT
| INTEGER
| BOOLEAN
| LPAREN expr RPAREN
: IDENTIFIER { $$ = $1; }
| FLOAT { $$ = $1; }
| INTEGER { $$ = $1; }
| BOOLEAN { $$ = $1; }
| LPAREN expr RPAREN { $$ = $2; }
;
%%