@lang:str.at

Access a character by index in a string.

On-chain (@lang:str.at!): Selects one byte, so a multi-byte UTF-8 character is not returned whole.

Returns: string

Syntax

@lang:str.at(value index)

Arguments

Name	Type	Description
value	string	Source string
index	number	Zero-based character index (negative counts from the end)

See Also

• @str.slice — extract a substring
• @at — array element access

On-chain face (@str.at!)

Select a single byte of the string return of a call as a one-byte slice, on-chain. A negative index resolves against the live byte length (-1 is the last byte).

Examples

load lang

set $pool 0x44fA8E6f47987339850636F88629646662444217

assert @str.at!($pool::{symbol()(string)} 0) == "W"
assert @str.at!($pool::{symbol()(string)} -1) == "H"

Notes

• Byte semantics: for ASCII strings this is the character at the index; a multi-byte UTF-8 character yields one of its bytes.
• An out-of-range index reverts with SliceOutOfBounds at assertion time.

See Also

• assert, @str.slice!