====== go:templating:go_html_template_range ======

Go html/template (range loop)

Note: html/template is a Go (Golang) standard library. The idea of “looping in templates” is similar to PHP templating engines (Blade/Twig).

===== What it is =====

In Go html/template, the action used to loop over a slice/array/map is:

{{range .}} ... {{end}}

range iterates over the data (e.g., a slice) and renders the inside block once per element.

. (dot) is the “current context”. Inside range, . becomes the current item.

===== What it’s for =====

Render lists in HTML: menus, table rows, cards, comments, products, etc.

Iterate over a map to output key/value.

Handle empty lists using else.

===== Examples =====

1) Simple slice loop

{{range .}}
  <li>{{.}}</li>
{{end}}


If you pass []string{"a", "b"}, you’ll get two <li> items.

2) Index + item

{{range $i, $item := .}}
  <div>{{$i}} - {{$item}}</div>
{{end}}


3) Loop over a slice of structs

Assume your data is []User:

{{range .}}
  <p>Name: {{.Name}} | Email: {{.Email}}</p>
{{end}}


4) Empty list handling (else)

{{range .}}
  <li>{{.}}</li>
{{else}}
  <li>No items</li>
{{end}}


===== Key points =====

The correct loop syntax is {{range .}} ... {{end}}.

Inside range, . becomes the current element.

You can bind variables: {{range $i, $v := .}} ... {{end}}.

You can add {{else}} to handle empty collections.

===== Hard words (with IPA + Vietnamese) =====

template /ˈtɛm.plət/: mẫu giao diện / khuôn render

action /ˈæk.ʃən/: hành động (cú pháp lệnh trong template)

range /reɪndʒ/: lặp / duyệt qua

slice /slaɪs/: mảng động trong Go (danh sách thay đổi độ dài)

context /ˈkɒn.tekst/: ngữ cảnh (dữ liệu mà . đang trỏ tới)