You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: file.go
    path of file: ./repos/plumber/vendor/github.com/jhump/protoreflect/desc/protoparse/ast
    
    the code of the file until where you have to start completion: package ast

import "fmt"

// FileDeclNode is a placeholder interface for AST nodes that represent files.
// This allows NoSourceNode to be used in place of *FileNode for some usages.
type FileDeclNode interface {
	Node
	GetSyntax() Node
}

var _ FileDeclNode = (*FileNode)(nil)
var _ Fi
    
func NewSyntaxNode(keyword *KeywordNode, equals *RuneNode, syntax StringValueNode, semicolon *RuneNode) *SyntaxNode {
	if keyword == nil {
		panic("keyword is nil")
	}
	if equals == nil {
		panic("equals is nil")
	}
	if syntax == nil {
		panic("syntax is nil")
	}
	if semicolon == nil {
		panic("semicolon is nil")
	}
	children := []Node{keyword, equals, syntax, semicolon}
	return &SyntaxNode{
		compositeNode: compositeNode{
			children: children,
		},
		Keyword:   keyword,
		Equals:    equals,
		Syntax:    syntax,
		Semicolon: semicolon,
	}
}