51 this(Lexer lex) 51 this(Lexer lex) 52 { 52 { 53 this.lex = lex; 53 this.lex = lex; 54 } 54 } 55 55 56 Program parseProgram() 56 Program parseProgram() 57 { 57 { > 58 Program p = parseStatements(); > 59 if( !lex.empty ) { > 60 auto e = ParserException.create(lex, "cannot reach eof") > 61 throw e; > 62 } > 63 return p; > 64 } > 65 > 66 Program parseStatements() > 67 { 58 Program p; 68 Program p; 59 while( !lex.empty ) | 69 while( !lex.empty && (lex.front.kind!=Token.Kind.identifier || l 60 p ~= parseStatement(); 70 p ~= parseStatement(); 61 return p; 71 return p; 62 } 72 } 63 73 64 Statement parseStatement() 74 Statement parseStatement() 65 { 75 { 66 auto saved = lex.save; 76 auto saved = lex.save; ................................................................................................................................................................................ 183 } 193 } 184 if( tryEat("(") ) 194 if( tryEat("(") ) 185 { 195 { 186 auto e = parseE(); 196 auto e = parseE(); 187 eat(")", "after parenthesized expression"); 197 eat(")", "after parenthesized expression"); 188 return e; 198 return e; 189 } 199 } > 200 if( tryEat("if") ) > 201 { > 202 eat("(", "after if"); > 203 auto cond = parseE(); > 204 eat(")", "after if condition"); > 205 auto thenPos = lex.front.pos; > 206 eat("{", "after if condition"); > 207 Statement[] th = parseStatements(); > 208 eat("}", "after if-then body"); > 209 Statement[] el; > 210 auto elsePos = lex.front.pos; > 211 if( tryEat("else") ) { > 212 eat("{", "after else"); > 213 el = parseStatements(); > 214 eat("}", "after else body"); > 215 } > 216 return new FuncallExpression(pos, > 217 new VarExpression(pos, "if"), > 218 cond, > 219 new FunLiteralExpression(thenPos, [], th), > 220 new FunLiteralExpression(elsePos, [], el) > 221 ); > 222 } 190 223 191 if( tryEat("fun") ) 224 if( tryEat("fun") ) 192 { 225 { 193 eat("(", "after fun"); 226 eat("(", "after fun"); 194 string[] params; 227 string[] params; 195 while(!tryEat(")")) 228 while(!tryEat(")")) 196 { 229 { ................................................................................................................................................................................ 311 )))); 344 )))); 312 } 345 } 313 unittest 346 unittest 314 { 347 { 315 auto p = parserFromString(`var x = 1; var f = fun(){x=x+1;}; f(); f(); x 348 auto p = parserFromString(`var x = 1; var f = fun(){x=x+1;}; f(); f(); x 316 Program prog = p.parseProgram(); 349 Program prog = p.parseProgram(); 317 } 350 } > 351 > 352 unittest > 353 { > 354 auto p = parserFromString(`if(x<2){1;}else{x;};`); > 355 Program prog = p.parseProgram(); > 356 assert( prog[0] == new ExprStatement(null, new FuncallExpression(null, > 357 new VarExpression(null, "if"), > 358 new FuncallExpression(null, new VarExpression(null,"<"), new Var > 359 new IntLiteralExpression(null, BigInt(2))), > 360 new FunLiteralExpression(null, [], [new ExprStatement(null, new > 361 new FunLiteralExpression(null, [], [new ExprStatement(null, new > 362 ))); > 363 }