Esempio n. 1
0
// VisitExpression implements corresponding Visitor interface method
func (v *evalVisitor) VisitExpression(node *ast.Expression) interface{} {
	v.at(node)

	var result interface{}
	done := false

	v.pushExpr(node)

	// helper call
	if helperName := node.HelperName(); helperName != "" {
		if helper := v.findHelper(helperName); helper != zero {
			result = v.callHelper(helperName, helper, node)
			done = true
		}
	}

	if !done {
		// literal
		if literal, ok := node.LiteralStr(); ok {
			if val := v.evalField(v.curCtx(), literal, true); val.IsValid() {
				result = val.Interface()
				done = true
			}
		}
	}

	if !done {
		// field path
		if path := node.FieldPath(); path != nil {
			// @todo Find a cleaner way ! Don't break the pattern !
			// this is an exception to visitor pattern, because we need to pass the info
			// that this path is at root of current expression
			if val := v.evalPathExpression(path, true); val != nil {
				result = val
			}
		}
	}

	v.popExpr()

	return result
}
Esempio n. 2
0
// isHelperCall returns true if given expression is a helper call
func (v *evalVisitor) isHelperCall(node *ast.Expression) bool {
	if helperName := node.HelperName(); helperName != "" {
		return v.findHelper(helperName) != zero
	}
	return false
}