tiger/src/lib/tiger/tiger_parser.mly

   1 %{
   2   open Printf
   3 %}
   4
   5 /* Declarations */
   6 %token AND
   7 %token ARRAY
   8 %token ASSIGN
   9 %token BREAK
  10 %token COLON
  11 %token COMMA
  12 %token DIVIDE
  13 %token DO
  14 %token DOT
  15 %token ELSE
  16 %token END
  17 %token EOF
  18 %token EQ
  19 %token FOR
  20 %token FUNCTION
  21 %token GE
  22 %token GT
  23 %token <string> ID
  24 %token IF
  25 %token IN
  26 %token <int> INT
  27 %token LBRACE
  28 %token LBRACK
  29 %token LE
  30 %token LET
  31 %token LPAREN
  32 %token LT
  33 %token MINUS
  34 %token NEQ
  35 %token NIL
  36 %token OF
  37 %token OR
  38 %token PLUS
  39 %token RBRACE
  40 %token RBRACK
  41 %token RPAREN
  42 %token SEMICOLON
  43 %token <string> STRING
  44 %token THEN
  45 %token TIMES
  46 %token TO
  47 %token TYPE
  48 %token VAR
  49 %token WHILE
  50
  51 /* from lowest precedence */
  52 %left OR
  53 %left AND
  54 %nonassoc EQ NEQ GT LT GE LE
  55 %left PLUS MINUS
  56 %left TIMES DIVIDE
  57 %nonassoc UMINUS
  58 /* to highest precedence */
  59
  60 %type <string> program
  61
  62 %start program
  63
  64 %%
  65
  66 program:
  67   | exp EOF
  68     {
  69       sprintf "program[%s]" $1
  70     }
  71
  72 exp:
  73   | NIL
  74     {
  75       "nil[]"
  76     }
  77   | INT
  78     {
  79       sprintf "int[%d]" $1
  80     }
  81   | MINUS exp %prec UMINUS
  82     {
  83       sprintf "negation[%s]" $2
  84     }
  85   | ID LBRACK exp RBRACK OF exp
  86     {
  87       let type_id = $1 in
  88       let exp_1 = $3 in
  89       let exp_2 = $6 in
  90       sprintf "array[type[%s], size[%s], val[%s]]" type_id exp_1 exp_2
  91     }
  92   | ID LBRACE rec_field_assignments RBRACE
  93     {
  94       let type_id = $1 in
  95       let rec_field_assignments = $3 in
  96       sprintf
  97         "record[type[%s], rec_field_assignments[%s]]"
  98         type_id rec_field_assignments
  99     }
 100   | lvalue
 101     {
 102       $1
 103     }
 104   | lvalue ASSIGN exp
 105     {
 106       sprintf "assign[%s := %s]" $1 $3
 107     }
 108   | STRING
 109     {
 110       sprintf "string[%S]" $1
 111     }
 112   | ID unit
 113     {
 114       let id = $1 in
 115       sprintf "fun_call[%s, []]" id
 116     }
 117   | ID LPAREN fun_args RPAREN
 118     {
 119       let id = $1 in
 120       let fun_args = $3 in
 121       sprintf "fun_call[%s, %s]" id fun_args
 122     }
 123   | exp op exp
 124     {
 125       sprintf "op[%s %s %s]" $1 $2 $3
 126     }
 127   | IF exp THEN exp ELSE exp
 128     {
 129       let e1 = $2 in
 130       let e2 = $4 in
 131       let e3 = $6 in
 132       sprintf "if_then_else[%s, then[%s], else[%s]]" e1 e2 e3
 133     }
 134   | IF exp THEN exp
 135     {
 136       sprintf "if_then[%s, then[%s]]" $2 $4
 137     }
 138   | WHILE exp DO exp
 139     {
 140       sprintf "while[%s, do[%s]]" $2 $4
 141     }
 142   | FOR ID ASSIGN exp TO exp DO exp
 143     {
 144       let id = $2 in
 145       let e1 = $4 in
 146       let e2 = $6 in
 147       let e3 = $8 in
 148       sprintf "for[%s := %s, to[%s], do[%s]]" id e1 e2 e3
 149     }
 150   | BREAK
 151     {
 152       "break[]"
 153     }
 154   | LPAREN seq RPAREN
 155     {
 156       sprintf "seq[%s]" $2
 157     }
 158   | LET decs IN seq END
 159     {
 160       let decs = $2 in
 161       let seq = $4 in
 162       sprintf "let[decs[%s], in[seq[%s]]]" decs seq
 163     }
 164   | unit
 165     {
 166       $1
 167     }
 168
 169 seq:
 170   | exp
 171     {
 172       sprintf "%s" $1
 173     }
 174   | exp SEMICOLON seq
 175     {
 176       sprintf "%s; %s" $1 $3
 177     }
 178
 179 decs:
 180   | dec
 181     {
 182       sprintf "%s" $1
 183     }
 184   | dec decs
 185     {
 186       sprintf "%s %s" $1 $2
 187     }
 188
 189 dec:
 190   | tydec  {$1}
 191   | vardec {$1}
 192   | fundec {$1}
 193
 194 fundec:
 195   | FUNCTION ID unit EQ exp
 196     {
 197       let id       = $2 in
 198       let exp      = $5 in
 199       sprintf "fundec[%s, exp[%s]]" id exp
 200     }
 201   | FUNCTION ID LPAREN tyfields RPAREN EQ exp
 202     {
 203       let id       = $2 in
 204       let tyfields = $4 in
 205       let exp      = $7 in
 206       sprintf "fundec[%s, tyfields[%s], exp[%s]]" id tyfields exp
 207     }
 208   | FUNCTION ID LPAREN tyfields RPAREN COLON ID EQ exp
 209     {
 210       let id       = $2 in
 211       let tyfields = $4 in
 212       let type_id  = $7 in
 213       let exp      = $9 in
 214       sprintf
 215         "fundec[%s, tyfields[%s], type_id[%s], exp[%s]]"
 216         id tyfields type_id exp
 217     }
 218
 219 vardec:
 220   | VAR ID ASSIGN exp
 221     {
 222       let id = $2 in
 223       let exp = $4 in
 224       sprintf "vardec[%s, exp[%s]]" id exp
 225     }
 226   | VAR ID COLON ID ASSIGN exp
 227     {
 228       let id = $2 in
 229       let type_id = $4 in
 230       let exp = $6 in
 231       sprintf "vardec[%s, type_id[%s], exp[%s]]" id type_id exp
 232     }
 233
 234 tydec:
 235   | TYPE ID EQ ty
 236     {
 237       let type_id = $2 in
 238       let ty = $4 in
 239       sprintf "tydec[%s, %s]" type_id ty
 240     }
 241
 242 ty:
 243   | ID
 244     {
 245       let type_id = $1 in
 246       sprintf "type[type_id[%S]]" type_id
 247     }
 248   | LBRACE RBRACE
 249     {
 250       "record[]"
 251     }
 252   | LBRACE tyfields RBRACE
 253     {
 254       let tyfields = $2 in
 255       sprintf "record[%s]" tyfields
 256     }
 257   | ARRAY OF ID
 258     {
 259       let type_id = $3 in
 260       sprintf "array_of_type[%s]" type_id
 261     }
 262
 263 tyfields:
 264 /*| epsilon */
 265   | tyfield
 266     {$1}
 267   | tyfield COMMA tyfields
 268     {
 269       let tyfield = $1 in
 270       let tyfields = $3 in
 271       sprintf "%s, %s" tyfield tyfields
 272     }
 273
 274 tyfield:
 275   | ID COLON ID
 276     {
 277       let id = $1 in
 278       let type_id = $3 in
 279       sprintf "tyfield[%s, %s]" id type_id
 280     }
 281
 282 /* Perhaps "void"? */
 283 unit:
 284   | LPAREN RPAREN
 285     {
 286       "unit[]"
 287     }
 288
 289 rec_field_assignments:
 290   | ID EQ exp
 291     {
 292       let id = $1 in
 293       let exp = $3 in
 294       sprintf "%S = %s" id exp
 295     }
 296   | ID EQ exp COMMA rec_field_assignments
 297     {
 298       let id = $1 in
 299       let exp = $3 in
 300       let rec_field_assignments = $5 in
 301       sprintf "%S = %s, %s" id exp rec_field_assignments
 302     }
 303
 304 fun_args:
 305   | exp
 306     {
 307       $1
 308     }
 309   | exp COMMA fun_args
 310     {
 311       sprintf "%s, %s" $1 $3
 312     }
 313
 314 op:
 315   | PLUS   {"+"}
 316   | MINUS  {"-"}
 317   | TIMES  {"*"}
 318   | DIVIDE {"/"}
 319   | EQ     {"="}
 320   | NEQ    {"<>"}
 321   | GT     {">"}
 322   | LT     {"<"}
 323   | GE     {">="}
 324   | LE     {"<="}
 325   | AND    {"&"}
 326   | OR     {"|"}
 327
 328 lvalue:
 329   | ID
 330     {
 331       let id = $1 in
 332       sprintf "lvalue[%s]" id
 333     }
 334   | lvalue DOT ID
 335     {
 336       let record = $1 in
 337       let field = $3 in
 338       sprintf "get_record_field[%s, %s]" record field
 339     }
 340   | lvalue LBRACK exp RBRACK
 341     {
 342       let array = $1 in
 343       let subscript = $3 in
 344       sprintf "get_array_subscript[%s, %s]" array subscript
 345     }
 346
 347 %%