@lang:lookup

Look up an entry by name in a record ([a:1 b:2] or [name value] pairs).

On-chain (@lang:lookup!): The record is a @zip!/@enumerate! word-pair payload, string names travel as keccak digests, and a missing name reverts.

Returns: any

Syntax

@lang:lookup(record name)

Arguments

Name	Type	Description
record	record	Record (entries array) to look the name up in
name	string	Entry name to look up

On-chain face (@lookup!)

The value at wordIndexOf(keys, key) of an on-chain record: the record — a zipped key/value word-pair payload, see @keys for the representation — splits into its key and value lanes through unzipWords, wordIndexOf finds the key's pair index, and a word-index read of the value lane selects the value.

Keys follow the record representation: a build-time literal STRING key is keccak-hashed at composition time, a live string/bytes key hashes on-chain through hash (the digest path), and word keys (numbers, addresses, bytes32) travel as themselves.

Examples

load lang

set $vault 0x44fA8E6f47987339850636F88629646662444217

# The cap at index 2 of the enumeration
assert @lookup!(@enumerate!($vault::{caps()(uint256[])}) 2) >= 100

Notes

• A MISSING KEY REVERTS the assertion: wordIndexOf's not-found sentinel is the lane's word count, which pushes the value read out of bounds. The off-chain @lookup raises its "no entry named" error at run time instead.
• The value is an untyped word (compared as a number/word).

See Also

• assert, @keys!, @values!, @enumerate!, @zip!