/*
* Copyright 2002-2015 the original author or authors.
*
* Licensed 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.
*/
import {SpelNode} from './SpelNode';
import {Stack} from '../lib/Stack';
/**
* A function reference is of the form "#someFunction(a,b,c)". Functions may be defined in
* the context prior to the expression being evaluated or within the expression itself
* using a lambda function definition. For example: Lambda function definition in an
* expression: "(#max = {|x,y|$x>$y?$x:$y};max(2,3))" Calling context defined function:
* "#isEven(37)". Functions may also be static java methods, registered in the context
* prior to invocation of the expression.
*
* <p>Functions are very simplistic, the arguments are not part of the definition (right
* now), so the names must be unique.
*
* @author Andy Clement
* @author Ben March
* @since 0.2.0
*/
function createNode(functionName, position, args) {
var node = SpelNode.create('function', position);
node.getRaw = function () {
return {
functionName,
args
};
};
node.getValue = function (state) {
var locals = state.locals || {},
context = state.rootContext,
compiledArgs = [];
//populate arguments
args.forEach(function (arg) {
// reset the active context to root context for evaluating argument
const currentActiveContext = state.activeContext
state.activeContext = new Stack();
state.activeContext.push(state.rootContext);
// evaluate argument
compiledArgs.push(arg.getValue(state));
// reset the active context
state.activeContext = currentActiveContext;
});
if (Elocals[functionName]) {
return locals[functionName].apply(context, compiledArgs);
}
throw {
name: 'FunctionDoesNotExistException',
message: 'Function \'' + functionName + '\' does not exist.'
};
};
return node;
}
export var FunctionReference = {
create: createNode
};
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