language · keyword ·

requires

Declare a precondition

complete-programcpufunctionskeywordyeho

Use contracts at important boundaries where callers and maintainers need one visible definition of correctness.

requires

Status: experimental

Contract pass

Use contracts at important boundaries where callers and maintainers need one visible definition of correctness.

cpu · complete-program · type checked

Increment(int value) returns int
requires(value > 0)
ensures(result == value + 1)
{
    return value + 1
}

Console.Log(Text.From(Increment(4)))
project.mech
package = "tests.compiler.errorsTasksEffects.contractPass"
version = "0.1.0"
backend = "cpu-oracle"
osTarget = "windows"
archTarget = "x64"
selfContainedApp = false
Notes and source

Errors and contracts are experimental in the current conformance edition.

Keep the condition deterministic and cheap enough to be useful as evidence.

yeho/parser_declarations.cpp parseContractClauses and parseThingInvariant; conformance errors-contracts