gossamer
Top-level cross-runtime APIs: timers, base64, microtask
scheduling, and navigator info. Domain-specific APIs live in
submodules (see gossamer/url, gossamer/stream/readable_stream,
gossamer/fetch_extra, etc.).
Values
pub fn clear_interval(id: Int) -> NilCancels a repeating timer previously scheduled with set_interval.
pub fn clear_timeout(id: Int) -> NilCancels a one-shot timer previously scheduled with set_timeout.
pub fn decode_base64(encoded: String) -> Result(String, Nil)Decodes a base64-encoded string. Returns an error if the string is
not valid base64. Equivalent to JavaScript’s atob.
pub fn encode_base64(data: String) -> Result(String, Nil)Encodes a binary string as base64. Returns an error if data
contains code points beyond 0xFF (use
gleam/bit_array.base64_encode for arbitrary bytes). Equivalent to
JavaScript’s btoa.
pub fn hardware_concurrency() -> IntReturns the number of logical processors available to the runtime.
Useful for sizing worker pools. Some browsers cap this value for
fingerprinting protection. Equivalent to JavaScript’s
navigator.hardwareConcurrency.
pub fn queue_microtask(callback: fn() -> a) -> NilSchedules callback to run as a microtask — after the current
execution stack empties but before returning control to the event
loop.
pub fn set_interval(
delay: duration.Duration,
callback: fn() -> a,
) -> IntSchedules callback to run repeatedly every delay. Returns an id
that can be passed to clear_interval to cancel. Negative durations
are treated as zero.
pub fn set_timeout(
delay: duration.Duration,
callback: fn() -> a,
) -> IntSets a timer which executes callback once after delay elapses.
Returns an id that can be passed to clear_timeout to cancel.
Negative durations are treated as zero.
pub fn user_agent() -> StringReturns the runtime’s user agent string (e.g., browser identity,
Deno/Node version). Equivalent to JavaScript’s navigator.userAgent.