whether this line is the header record of an NDJSON image.
Deliberately a string test before it is a parse: the discriminating fields are written first
and the line can be hundreds of kilobytes, so there is no reason to build an object to answer
a question the first thirty characters already settle. The parse is the confirmation, not the
test, and it is only reached for a line that already looks like ours.
whether this line is the header record of an NDJSON image.
Deliberately a string test before it is a parse: the discriminating fields are written first and the line can be hundreds of kilobytes, so there is no reason to build an object to answer a question the first thirty characters already settle. The parse is the confirmation, not the test, and it is only reached for a line that already looks like ours.