@lang:sort

Sort an array: ascending by default, desc for descending, or by a comparator helper.

On-chain (@lang:sort!): Takes a direction rather than a comparator, and signed elements sort by value: the sign bit is flipped on the way in and back on the way out.

Returns: array

Syntax

@lang:sort(arr order?)

Arguments

Name	Type	Description
arr	array	Source array
[order]	helper | string	asc (default) or desc, or a comparator helper returning a number

See Also

• @reverse — reverse an array

On-chain face (@sort!)

Sort the array return of a call on-chain through sortWords, ascending by default and descending with a second argument:

load lang

set $safe 0x44fA8E6f47987339850636F88629646662444217

assert @at!(@sort!($safe::{caps()(uint256[])} desc) 0) >= 100

desc composes rather than adding anything on-chain: the array is sorted ascending and then reversed, which is one extra node and no new contract function.

Signed elements sort by VALUE, not by their raw word. Without that, every negative would land after every positive, because a two's-complement negative has its top bit set and reads as a huge unsigned number. The compiler flips the sign bit on the way in and back on the way out, which maps signed order onto unsigned order exactly and, unlike adding 2^255, cannot overflow a checked add. It costs two extra passes of one call per element, so it is only done when the elements are actually signed.

A comparator is refused. sortWords has no comparator hook, and a fold lambda cannot express one either: sorting is not a reduction over elements. Order by direction, and if you need a different key, @map! it into one first and sort that.

See Also

• assert, @unique!, @map!