@lang:str.includes

Check whether a string contains a substring (exact byte sequence, case-sensitive).

On-chain (@lang:str.includes!): The substring may be a live call; a constant one must be non-empty, since every string contains the empty string.

Returns: bool

Syntax

@lang:str.includes(value item)

Arguments

Name	Type	Description
value	string	Source string
item	string	Substring to search for

See Also

• @str.replace — find and replace
• @includes — array membership check

On-chain face (@str.includes!)

Whether the string return of a call contains a substring, checked on-chain — exact byte sequence, case-sensitive, no wildcards.

Examples

load lang

set $pool 0x44fA8E6f47987339850636F88629646662444217

# "Uniswap LP Token" contains "LP"
assert @str.includes!($pool::{name()(string)} "LP") == true

# The name must NOT mention a rebrand
assert @str.includes!($pool::{name()(string)} "Sushi") == false

Notes

• An empty part is rejected at build time when it is a constant — every string contains it, so the assertion could never fail. A LIVE part that resolves empty reports found at 0, which is the same answer stated honestly rather than a guard that cannot run.
• Matches the exact byte sequence: case-sensitive, no wildcards or regex; a multi-byte UTF-8 part matches its exact encoding.
• Boolean-valued: usable bare, compared with == true / == false, or nested inside @bool!(...) logic.

See Also

• assert, @str.charset!, @str.split!