Module file 

One entry’s bytes, through a writable stream.

Every write here opens a writable, writes, and closes it: the stream is a swap file the browser puts in place only when it is closed, so a reader caught between the calls sees what was there before rather than half of each.

Enums

Keeping 🔒

Whether the writable that is opened starts from what the file already holds.

Functions

append

Add to the end, which is how the manifest grows.

close 🔒

By value, because a stream that has been closed has nothing more to say and a second write to one is the browser’s refusal rather than ours.

opened 🔒

put 🔒

read

Errors

truncate

Errors

writable 🔒

write

Whole file or nothing.