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Built-in Functions


panic

fun panic(_ message: String): Never

Terminates the program unconditionally and reports a message which explains why the unrecoverable error occurred.

let optionalAccount: AuthAccount? = // ...
let account = optionalAccount ?? panic("missing account")

assert

fun assert(_ condition: Bool, message: String)

Terminates the program if the given condition is false, and reports a message which explains how the condition is false. Use this function for internal sanity checks.

The message argument is optional.

unsafeRandom

fun unsafeRandom(): UInt64

Returns a pseudo-random number.

NOTE: The use of this function is unsafe if not used correctly.

Follow best practices to prevent security issues when using this function.