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 %nonassoc ASSIGN
  53 %left OF DO
  54 %left OR
  55 %left AND
  56 %nonassoc EQ NEQ GT LT GE LE
  57 %left PLUS MINUS
  58 %left TIMES DIVIDE
  59 %nonassoc UMINUS
  60 /* to highest precedence */
  61
  62 %type <string> program
  63
  64 %start program
  65
  66 %%
  67
  68 program:
  69   | exp EOF
  70     {
  71       sprintf "program[%s]" $1
  72     }
  73   ;
  74
  75 exp:
  76   | NIL
  77     {
  78       "nil[]"
  79     }
  80   | INT
  81     {
  82       sprintf "int[%d]" $1
  83     }
  84   | MINUS exp %prec UMINUS
  85     {
  86       sprintf "negation[%s]" $2
  87     }
  88   | ID LBRACK exp RBRACK OF exp
  89     {
  90       let type_id = $1 in
  91       let number_of_elements = $3 in
  92       let initial_value = $6 in
  93       sprintf
  94         "array[type[%s], size[%s], val[%s]]"
  95         type_id number_of_elements initial_value
  96     }
  97   | ID LBRACE rec_field_assignments RBRACE
  98     {
  99       let type_id = $1 in
 100       let rec_field_assignments = $3 in
 101       sprintf
 102         "record[type[%s], rec_field_assignments[%s]]"
 103         type_id rec_field_assignments
 104     }
 105   | lvalue
 106     {
 107       $1
 108     }
 109   | lvalue ASSIGN exp
 110     {
 111       sprintf "assign[%s := %s]" $1 $3
 112     }
 113   | STRING
 114     {
 115       sprintf "string[%S]" $1
 116     }
 117   | ID LPAREN RPAREN
 118     {
 119       let id = $1 in
 120       sprintf "fun_call[%s, []]" id
 121     }
 122   | ID LPAREN fun_args RPAREN
 123     {
 124       let id = $1 in
 125       let fun_args = $3 in
 126       sprintf "fun_call[%s, %s]" id fun_args
 127     }
 128   | exp op exp
 129     {
 130       sprintf "op[%s %s %s]" $1 $2 $3
 131     }
 132   | IF exp THEN exp ELSE exp
 133     {
 134       let e1 = $2 in
 135       let e2 = $4 in
 136       let e3 = $6 in
 137       sprintf "if_then_else[%s, then[%s], else[%s]]" e1 e2 e3
 138     }
 139   | IF exp THEN exp
 140     {
 141       sprintf "if_then[%s, then[%s]]" $2 $4
 142     }
 143   | WHILE exp DO exp
 144     {
 145       sprintf "while[%s, do[%s]]" $2 $4
 146     }
 147   | FOR ID ASSIGN exp TO exp DO exp
 148     {
 149       let id = $2 in
 150       let e1 = $4 in
 151       let e2 = $6 in
 152       let e3 = $8 in
 153       sprintf "for[%s := %s, to[%s], do[%s]]" id e1 e2 e3
 154     }
 155   | BREAK
 156     {
 157       "break[]"
 158     }
 159   | LPAREN exps RPAREN
 160     {
 161       sprintf "exps[%s]" $2
 162     }
 163   | LET decs IN exps END
 164     {
 165       let decs = $2 in
 166       let exps = $4 in
 167       sprintf "let[decs[%s], in[exps[%s]]]" decs exps
 168     }
 169   | LPAREN RPAREN
 170     {
 171       (* Perhaps "void"? *)
 172       "unit[]"
 173     }
 174   ;
 175
 176 rec_field_assignments:
 177   | ID EQ exp
 178     {
 179       let id = $1 in
 180       let exp = $3 in
 181       sprintf "%S = %s" id exp
 182     }
 183   | ID EQ exp COMMA rec_field_assignments
 184     {
 185       let id = $1 in
 186       let exp = $3 in
 187       let rec_field_assignments = $5 in
 188       sprintf "%S = %s, %s" id exp rec_field_assignments
 189     }
 190   ;
 191
 192 exps:
 193   | exp
 194     {
 195       let exp = $1 in
 196       sprintf "%s" exp
 197     }
 198   | exp SEMICOLON exps
 199     {
 200       let exp = $1 in
 201       let exps = $3 in
 202       sprintf "%s; %s" exp exps
 203     }
 204   ;
 205
 206 decs:
 207   | dec
 208     {
 209       sprintf "%s" $1
 210     }
 211   | dec decs
 212     {
 213       sprintf "%s %s" $1 $2
 214     }
 215   ;
 216
 217 dec:
 218   /* Tydec */
 219   | TYPE ID EQ ID
 220     {
 221       let type_id_new = $2 in
 222       let type_id_orig = $4 in
 223       sprintf "tydec_alias[from[%s], to[%s]]" type_id_new type_id_orig
 224     }
 225   | TYPE ID EQ LBRACE RBRACE
 226     {
 227       let type_id = $2 in
 228       sprintf "tydec_empty_record[%s]" type_id
 229     }
 230   | TYPE ID EQ LBRACE tyfields RBRACE
 231     {
 232       let type_id = $2 in
 233       let tyfields = $5 in
 234       sprintf "tydec_record[%s, fields[%s]]" type_id tyfields
 235     }
 236   | TYPE ID EQ ARRAY OF ID
 237     {
 238       let type_id = $2 in
 239       let element_type_id = $6 in
 240       sprintf "tydec_array[%s, elements_of_type[%s]]" type_id element_type_id
 241     }
 242
 243   /* Vardec */
 244   | VAR ID ASSIGN exp
 245     {
 246       let id = $2 in
 247       let exp = $4 in
 248       sprintf "vardec[%s, exp[%s]]" id exp
 249     }
 250   | VAR ID COLON ID ASSIGN exp
 251     {
 252       let id = $2 in
 253       let type_id = $4 in
 254       let exp = $6 in
 255       sprintf "vardec[%s, type_id[%s], exp[%s]]" id type_id exp
 256     }
 257
 258   /* Fundec */
 259   | FUNCTION ID LPAREN RPAREN EQ exp
 260     {
 261       let id       = $2 in
 262       let exp      = $6 in
 263       sprintf "fundec[%s, arguments[], exp[%s]]" id exp
 264     }
 265   | FUNCTION ID LPAREN tyfields RPAREN EQ exp
 266     {
 267       let id       = $2 in
 268       let tyfields = $4 in
 269       let exp      = $7 in
 270       sprintf "fundec[%s, arguments[%s], exp[%s]]" id tyfields exp
 271     }
 272   | FUNCTION ID LPAREN tyfields RPAREN COLON ID EQ exp
 273     {
 274       let id       = $2 in
 275       let tyfields = $4 in
 276       let type_id  = $7 in
 277       let exp      = $9 in
 278       sprintf
 279         "fundec[%s, tyfields[%s], type_id[%s], exp[%s]]"
 280         id tyfields type_id exp
 281     }
 282   ;
 283
 284 tyfields:
 285   | ID COLON ID
 286     {
 287       let id_1 = $1 in
 288       let id_2 = $3 in
 289       sprintf "%s : %s" id_1 id_2
 290     }
 291   | ID COLON ID COMMA tyfields
 292     {
 293       let id_1 = $1 in
 294       let id_2 = $3 in
 295       let tyfield = sprintf "%s : %s" id_1 id_2 in
 296       let tyfields = $5 in
 297       sprintf "%s, %s" tyfield tyfields
 298     }
 299   ;
 300
 301 fun_args:
 302   | exp
 303     {
 304       $1
 305     }
 306   | exp COMMA fun_args
 307     {
 308       sprintf "%s, %s" $1 $3
 309     }
 310   ;
 311
 312 op:
 313   | PLUS   {"+"}
 314   | MINUS  {"-"}
 315   | TIMES  {"*"}
 316   | DIVIDE {"/"}
 317   | EQ     {"="}
 318   | NEQ    {"<>"}
 319   | GT     {">"}
 320   | LT     {"<"}
 321   | GE     {">="}
 322   | LE     {"<="}
 323   | AND    {"&"}
 324   | OR     {"|"}
 325   ;
 326
 327 lvalue:
 328   | ID lvalue_part
 329     {
 330       let id = $1 in
 331       let part = $2 in
 332       sprintf "lvalue[%s, part[%s]]" id part
 333     }
 334   ;
 335
 336 lvalue_part:
 337   | {"epsilon[]"}
 338   | lvalue_subscript {$1}
 339   | lvalue_field_access {$1}
 340   ;
 341
 342 lvalue_subscript:
 343   | LBRACK exp RBRACK
 344     {
 345       let exp = $2 in
 346       sprintf "subscript[%s]" exp
 347     }
 348   ;
 349
 350 lvalue_field_access:
 351   | DOT ID
 352     {
 353       let field = $2 in
 354       sprintf "field_access[%s]" field
 355     }
 356   ;
 357
 358 %%