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   | fun_call
 113     {
 114       $1
 115     }
 116   | exp op exp
 117     {
 118       sprintf "op[%s %s %s]" $1 $2 $3
 119     }
 120   | IF exp THEN exp ELSE exp
 121     {
 122       let e1 = $2 in
 123       let e2 = $4 in
 124       let e3 = $6 in
 125       sprintf "if_then_else[%s, then[%s], else[%s]]" e1 e2 e3
 126     }
 127   | IF exp THEN exp
 128     {
 129       sprintf "if_then[%s, then[%s]]" $2 $4
 130     }
 131   | WHILE exp DO exp
 132     {
 133       sprintf "while[%s, do[%s]]" $2 $4
 134     }
 135   | FOR id ASSIGN exp TO exp DO exp
 136     {
 137       let id = $2 in
 138       let e1 = $4 in
 139       let e2 = $6 in
 140       let e3 = $8 in
 141       sprintf "for[%s := %s, to[%s], do[%s]]" id e1 e2 e3
 142     }
 143   | BREAK
 144     {
 145       "break[]"
 146     }
 147   | LPAREN seq RPAREN
 148     {
 149       sprintf "seq[%s]" $2
 150     }
 151   | LET decs IN seq END
 152     {
 153       let decs = $2 in
 154       let seq = $4 in
 155       sprintf "let[decs[%s], in[seq[%s]]]" decs seq
 156     }
 157   | unit
 158     {
 159       $1
 160     }
 161
 162 seq:
 163   | exp
 164     {
 165       sprintf "%s" $1
 166     }
 167   | exp SEMICOLON seq
 168     {
 169       sprintf "%s; %s" $1 $3
 170     }
 171
 172 decs:
 173   | dec
 174     {
 175       sprintf "%s" $1
 176     }
 177   | dec decs
 178     {
 179       sprintf "%s %s" $1 $2
 180     }
 181
 182 dec:
 183   | tydec  {$1}
 184   | vardec {$1}
 185   | fundec {$1}
 186
 187 fundec:
 188   | FUNCTION id unit EQ exp
 189     {
 190       let id       = $2 in
 191       let exp      = $5 in
 192       sprintf "fundec[%s, exp[%s]]" id exp
 193     }
 194   | FUNCTION id LPAREN tyfields RPAREN EQ exp
 195     {
 196       let id       = $2 in
 197       let tyfields = $4 in
 198       let exp      = $7 in
 199       sprintf "fundec[%s, tyfields[%s], exp[%s]]" id tyfields exp
 200     }
 201   | FUNCTION id LPAREN tyfields RPAREN COLON ID EQ exp
 202     {
 203       let id       = $2 in
 204       let tyfields = $4 in
 205       let type_id  = $7 in
 206       let exp      = $9 in
 207       sprintf
 208         "fundec[%s, tyfields[%s], type_id[%s], exp[%s]]"
 209         id tyfields type_id exp
 210     }
 211
 212 vardec:
 213   | VAR id ASSIGN exp
 214     {
 215       let id = $2 in
 216       let exp = $4 in
 217       sprintf "vardec[%s, exp[%s]]" id exp
 218     }
 219   | VAR id COLON ID ASSIGN exp
 220     {
 221       let id = $2 in
 222       let type_id = $4 in
 223       let exp = $6 in
 224       sprintf "vardec[%s, type_id[%s], exp[%s]]" id type_id exp
 225     }
 226
 227 tydec:
 228   | TYPE ID EQ ty
 229     {
 230       let type_id = $2 in
 231       let ty = $4 in
 232       sprintf "tydec[%s, %s]" type_id ty
 233     }
 234
 235 ty:
 236   | ID
 237     {
 238       let type_id = $1 in
 239       sprintf "type[type_id[%S]]" type_id
 240     }
 241   | LBRACE RBRACE
 242     {
 243       "record[]"
 244     }
 245   | LBRACE tyfields RBRACE
 246     {
 247       let tyfields = $2 in
 248       sprintf "record[%s]" tyfields
 249     }
 250   | ARRAY OF ID
 251     {
 252       let type_id = $3 in
 253       sprintf "array_of_type[%s]" type_id
 254     }
 255
 256 tyfields:
 257 /*| epsilon */
 258   | tyfield
 259     {$1}
 260   | tyfield COMMA tyfields
 261     {
 262       let tyfield = $1 in
 263       let tyfields = $3 in
 264       sprintf "%s, %s" tyfield tyfields
 265     }
 266
 267 tyfield:
 268   | id COLON ID
 269     {
 270       let id = $1 in
 271       let type_id = $3 in
 272       sprintf "tyfield[%s, %s]" id type_id
 273     }
 274
 275 id:
 276   | ID
 277     {
 278       sprintf "id[%S]" $1
 279     }
 280
 281 /* Perhaps "void"? */
 282 unit:
 283   | LPAREN RPAREN
 284     {
 285       "unit[]"
 286     }
 287
 288 rec_field_assignments:
 289   | id EQ exp
 290     {
 291       sprintf "%S = %s" $1 $3
 292     }
 293   | id EQ exp COMMA rec_field_assignments
 294     {
 295       sprintf "%S = %s, %s" $1 $3 $5
 296     }
 297
 298 fun_call:
 299   | id unit
 300     {
 301       sprintf "fun_call[%s, %s]" $1 $2
 302     }
 303   | id LPAREN fun_args RPAREN
 304     {
 305       sprintf "fun_call[%s, %s]" $1 $3
 306     }
 307
 308 fun_args:
 309   | exp
 310     {
 311       $1
 312     }
 313   | exp COMMA fun_args
 314     {
 315       sprintf "%s, %s" $1 $3
 316     }
 317
 318 op:
 319   | PLUS   {"+"}
 320   | MINUS  {"-"}
 321   | TIMES  {"*"}
 322   | DIVIDE {"/"}
 323   | EQ     {"="}
 324   | NEQ    {"<>"}
 325   | GT     {">"}
 326   | LT     {"<"}
 327   | GE     {">="}
 328   | LE     {"<="}
 329   | AND    {"&"}
 330   | OR     {"|"}
 331
 332 lvalue:
 333   | id
 334     {
 335       sprintf "lvalue[%s]" $1
 336     }
 337   | lvalue DOT id
 338     {
 339       sprintf "get_record_field[%s, %s]" $1 $3
 340     }
 341   | lvalue LBRACK exp RBRACK
 342     {
 343       sprintf "get_array_subscript[%s, %s]" $1 $3
 344     }
 345
 346 %%