Standard library

Each of these is required by name — for example, require: brj: as(concurrent, c). brj.core is available everywhere without one.

brj.concurrent

Structured concurrency, on virtual threads.

spawn(f)

Starts a task running the zero-argument function f, and returns its future: c/spawn(#0: fetch(url)).

await(future)

Waits for a task, returning its result, or throwing what it threw.

interrupt(future)

Cancels a task, and the tasks it started.

ensureActive()

Throws Interrupted if the current task has been interrupted.

sleepMs(ms)

Sleeps for ms milliseconds; throws Interrupted if interrupted meanwhile.

Effects bound with withFx: apply within the tasks spawned inside it.

brj.time

now()

The current instant, a java.time.Instant.

inst(s)

Parses an ISO-8601 instant: inst("2026-01-01T00:00:00Z").

dur(s)

Parses an ISO-8601 duration: dur("PT30S").

durMs(ms), durSec(s)

A java.time.Duration of that many milliseconds, or seconds.

brj.fs

file(path)

A File for path.

exists(f), isFile(f), isDir(f)

Whether f exists; is a regular file; is a directory.

readString(f)

f’s contents, as a Str.

fromBytes(f)

f’s contents, as Bytes.

list(f)

The entries of the directory f, as Files.

resolve(f, name)

The File for name within f.

name(f), path(f)

f’s name; its full path.

brj.bytes

fromStr(s)

s encoded as UTF-8.

count(bs)

The number of bytes.

nth(bs, i)

The byte at i, as an Int from 0 to 255.

brj.str

fromBytes(bs)

bs decoded as UTF-8.

brj.rdr

The reader’s forms, as values. See macros and quoting.

fromStr(s)

The forms read from s, as a [Form].

fromFile(f)

The forms read from the file f.

SymbolForm, QSymbolForm, DotSymbolForm, QDotSymbolForm, List, Vector, Set, Record, Int, Double, String, BigInt, BigDec

The variants of the Form enum, with their keys .sym, .ns, .member, .els and .value.

.loc

A form’s source location, in its metadata, with .source, .path, .startLine, .startColumn, .endLine and .endColumn.

brj.test

Tests, run by Gradle’s test task through Bridje’s JUnit engine.

.test

Marks a zero-argument function as a test: ^t/.test def: arithmetic() ….

is(expr)

Records a failure, with the form of expr, if expr is false. A test passes if it records no failures and doesn’t throw.

runTest(qualifiedName)

Runs one test, returning a TestResult{.failures, .exn}, where each failure is a Failure{.form, .message}.