Lists

Overview

Lists are Echo's mutable ordered collection type.

Syntax

nums: list = [1, 2, 3];
first: int = nums[0];
nums[1] = 10;

Example

nums: list = [1, 2, 3];
nums.push(4);
nums.insertAt(1, 99);
nums.removeValue(2);
say(nums);

Output

[1, 99, 3, 4]

Notes

• Lists are mutable.
• Indexing requires an int.
• Nested indexing and nested assignment are supported.
• clone() returns a shallow copy.
• order() sorts ascending by default.
• order(cmpFn) uses a comparator function that returns int.

Common Mistakes

• Calling list methods on non-list values
• Using out-of-range indexes
• Assuming clone() is deep

See Also

• Built-in Methods
• Operators
• Lists in Practice