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List functions

enumerate

Converts the list to a new list of tuples. Each tuple contains the element's position in the original list and its value.

<% for tuple in [1, 2, 3].enumerate %>
    <%= tuple.0 %>. <%= tuple.1 %>
<% end %>

0. 1
1. 2
2. 3

reverse

Reverses the order of elements in the list. rev is an alias for reverse.

<% for value in [1, 2, 3].reverse %>
    <%= value %>
<% end %>

3
2
1

len

Returns the length of the list.

<%= [1, 2, 3].len %>

3

empty

Returns true if the list is empty (length 0).

<%= [1, 2, 3].empty %>

false