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: node.go
    path of file: ./repos/hugo/tpl/internal/go_templates/texttemplate/parse
    
    the code of the file until where you have to start completion: // Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Parse nodes.

package parse

import (
	"fmt"
	"strconv"
	"strings"
)

var textFormat = "%s" // Changed to "%q" in tests for better error messages.

// A Node is an element in the parse tree. The interface is trivial.
// The interface contains an unexported method so that only
// types local to this package can satisfy it.
type Node interface {
	Type() NodeType
	String() string
	// Copy does a deep copy of the Node and all its components.
	// To avoid type assertions, some XxxNodes also have specialized
	// CopyXxx methods that return *XxxNode.
	Copy() Node
	Position() Pos // byte position of start of node in full original input string
	// tree returns the containing *Tree.
	// It is unexported so all implementations of Node are in this package.
	tree() *Tree
	// writeTo writes the String output to the builder.
	writeTo(*strings.Builder)
}

// NodeType identifies the type of a parse tree node.
type NodeType int

// Pos represents a byte position in the original input text from which
// this template was parsed.
type Pos int

func (p Pos) Position() Pos {
	return p
}

// Type returns itself and provides an easy default implementation
// for embedding in a Node. Embedded in all non-trivial Nodes.
func (t NodeType) Type() NodeTyp
    
func (t *Tree) newNumber(pos Pos, text string, typ itemType) (*NumberNode, error) {
	n := &NumberNode{tr: t, NodeType: NodeNumber, Pos: pos, Text: text}
	switch typ {
	case itemCharConstant:
		rune, _, tail, err := strconv.UnquoteChar(text[1:], text[0])
		if err != nil {
			return nil, err
		}
		if tail != "'" {
			return nil, fmt.Errorf("malformed character constant: %s", text)
		}
		n.Int64 = int64(rune)
		n.IsInt = true
		n.Uint64 = uint64(rune)
		n.IsUint = true
		n.Float64 = float64(rune) // odd but those are the rules.
		n.IsFloat = true
		return n, nil
	case itemComplex:
		// fmt.Sscan can parse the pair, so let it do the work.
		if _, err := fmt.Sscan(text, &n.Complex128); err != nil {
			return nil, err
		}
		n.IsComplex = true
		n.simplifyComplex()
		return n, nil
	}
	// Imaginary constants can only be complex unless they are zero.
	if len(text) > 0 && text[len(text)-1] == 'i' {
		f, err := strconv.ParseFloat(text[:len(text)-1], 64)
		if err == nil {
			n.IsComplex = true
			n.Complex128 = complex(0, f)
			n.simplifyComplex()
			return n, nil
		}
	}
	// Do integer test first so we get 0x123 etc.
	u, err := strconv.ParseUint(text, 0, 64) // will fail for -0; fixed below.
	if err == nil {
		n.IsUint = true
		n.Uint64 = u
	}
	i, err := strconv.ParseInt(text, 0, 64)
	if err == nil {
		n.IsInt = true
		n.Int64 = i
		if i == 0 {
			n.IsUint = true // in case of -0.
			n.Uint64 = u
		}
	}
	// If an integer extraction succeeded, promote the float.
	if n.IsInt {
		n.IsFloat = true
		n.Float64 = float64(n.Int64)
	} else if n.IsUint {
		n.IsFloat = true
		n.Float64 = float64(n.Uint64)
	} else {
		f, err := strconv.ParseFloat(text, 64)
		if err == nil {
			// If we parsed it as a float but it looks like an integer,
			// it's a huge number too large to fit in an int. Reject it.
			if !strings.ContainsAny(text, ".eEpP") {
				return nil, fmt.Errorf("integer overflow: %q", text)
			}
			n.IsFloat = true
			n.Float64 = f
			// If a floating-point extraction succeeded, extract the int if needed.
			if !n.IsInt && float64(int64(f)) == f {
				n.IsInt = true
				n.Int64 = int64(f)
			}
			if !n.IsUint && float64(uint64(f)) == f {
				n.IsUint = true
				n.Uint64 = uint64(f)
			}
		}
	}
	if !n.IsInt && !n.IsUint && !n.IsFloat {
		return nil, fmt.Errorf("illegal number syntax: %q", text)
	}
	return n, nil
}