Namespaces

Bridje code is split into namespaces, one per file.

Files

A namespace’s name is its path on the classpath, with . for /: todo.model is todo/model.brj. In a Gradle project, sources are under src/main/bridje and tests under src/test/bridje.

A namespace is loaded the first time it’s required, and evaluated top to bottom, once. A definition can only refer to what’s defined above it.

The ns form

ns: name require: … import: …

Names the namespace, and declares what it uses. It must be the file’s first form; both clauses are optional.

ns: raft.server
  require:
    brj:
      as(concurrent, c)
      test
    raft:
      as(log, l)
  import:
    java.time:
      as(Instant, I)
      Duration

require:

Bridje namespaces, grouped under a package prefix. Within a prefix, as(name, alias) requires prefix.name as alias; a bare name requires it as name.

import:

Host classes, grouped under a package prefix, in the same way: as(Instant, I) imports java.time.Instant as I. See host interop.

A namespace with no ns: form is anonymous.

Qualified names

alias/name

A var, tag, enum or effect from a required namespace: c/spawn, l/Entry{…}.

alias/.key

A key from a required namespace.

full.ns.name/name

A var from a namespace by its full name, if it’s already loaded.

Alias/member, Alias/.member

A static or instance member of an imported class.

Unqualified names resolve to, in order: locals, the current namespace’s effects, brj.core’s effects, the current namespace’s definitions, brj.core’s definitions, imported classes, then host classes by their fully qualified name.

Running a namespace

A namespace that defines main can be run: main is called with the command-line arguments.

brj.main run namespace args…

Runs namespace’s main, from the classpath.

In Gradle, the BridjeExec task does the same:

tasks.register<BridjeExec>("run") {
    mainNamespace = "hello.core"
    args("--port", "8080")
}

Privacy

There’s no access control: every definition in a namespace is visible to anything that requires it. By convention, a name starting with _ is private.