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isErr

function isErr<T, E>(r): r is { error: E; ok: false };

Defined in: packages/engine/src/errors/Result.ts:51

Narrow a Result to its failure arm.

Type Parameter
T
E
ParameterTypeDescription
rResult<T, E>The result to test.

r is { error: E; ok: false }

True when it failed, narrowing r so r.error is reachable.