String (GrExpression expr, ExpressionContext expressionContext) { final DefaultGroovyVariableNameValidator nameValidator = new DefaultGroovyVariableNameValidator(expr, expressionContext.myUsedVarNames, true); final String[] varNames = GroovyNameSuggestionUtil.suggestVariableNames(expr, nameValidator); LOG.assertTrue(varNames.length > 0); expressionContext.myUsedVarNames.add(varNames[0]); return varNames[0]; }