| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| grammar MathEx; |
| |
| options { |
| language = Java; |
| } |
| |
| expression |
| : '(' expression ')' #parensExpression |
| | operator=('-' | '+') expression #unaryOperation |
| | operand0=expression operator='^' operand1=expression #binaryOperation |
| | operand0=expression operator=('*' | '%' | '/') operand1=expression #binaryOperation |
| | operand0=expression operator=('+' | '-') operand1=expression #binaryOperation |
| | variableName=IDENTIFIER #variable |
| | value=NUMBER #constant |
| | name=IDENTIFIER '(' ( expression (',' expression )* )? ')' #function |
| ; |
| |
| fragment CHAR : [a-zA-Z] ; |
| fragment DIGIT : [0-9] ; |
| fragment INT : [1-9] DIGIT* | DIGIT ; |
| fragment EXP : [Ee] [+\-]? INT ; |
| |
| NUMBER |
| : '-'? INT? '.' [0-9]+ EXP? // 1.35, 1.35E-9, 0.3, -4.5 |
| | '-'? INT EXP // 1e10 -3e4 |
| | '-'? INT // -3, 45 |
| ; |
| |
| WS : [ \t\n\r]+ -> skip ; |
| |
| PREC0_OP : [+\-] ; |
| PREC1_OP : [*%/] ; |
| PREC2_OP : '^' ; |
| |
| IDENTIFIER |
| : IDENTIFIER_START ( IDENTIFIER_MIDDLE* IDENTIFIER_END )? |
| ; |
| |
| fragment IDENTIFIER_START |
| : '_' |
| | [a-zA-Z] |
| ; |
| |
| fragment IDENTIFIER_MIDDLE |
| : '_' | '.' |
| | CHAR |
| | DIGIT |
| ; |
| |
| |
| fragment IDENTIFIER_END |
| : '_' |
| | CHAR |
| | DIGIT |
| ; |