In JavaScript sources, ReadableStream, ReadableStreamDefaultReader,
ReadableStreamDefaultController, CountQueuingStrategy and
ByteLengthQueuingStrategy (globals and node:stream/web exports) are class
values over a new runtime unit, scr_webstreams.c, which follows Node 24's
webstreams step by step: underlying sources, queuing strategies, default
readers, tee, ReadableStream.from and async iteration settle their promises
in Node's order. scr_dyn_handle_class.c gives a dyn handle tag a
constructor value with a prototype, brand checks and Node's constructor
errors. Stream state carries cycle headers, so the collector reclaims
streams whose callbacks close over their controllers.
Promise steps run as native promise reactions, a variant of scr_async.c
that only programs with web streams link; every other program links the
default object. TypeScript sources keep their static web stream lowerings.
Byte streams, BYOB readers, pipeTo and pipeThrough throw SC2020.
node24-web-stream-readers and node24-web-stream-readable-lifecycle now
match Node.
Without @types/node, every program loaded scriptc-node-fallback.d.ts whole:
the console and process globals and 47 Node modules, about 8,100 lines,
parsed, bound and checked in every cold build whether or not the program
imported them.
- The fallback file keeps the globals and the modules they name (console,
readline, readline/promises, perf_hooks, tty). Every other module, under
both spellings, has its own file in ambient/node-fallback/, which
references the files of the modules its declarations name.
- A module's file joins the program when one of the program's files names
the module in a string literal: imports, requires, import types and JSDoc
types all name modules that way. The entry is read before the first
program; the program-root discovery passes add modules that other files
name. Files are read as tsgo reads them, and the TypeScript libraries and
scriptc's own declarations are skipped.
- The checks that recognized the fallback file by its path recognize every
fallback file.
Chris Tate