Files
Paul Lewis 911c1b8a93 Updates node_modules
DISABLE_THIRD_PARTY_CHECK=Package needs updating with node_modules
Change-Id: I889f1b86c586e37307a3e13ad762aa56d1ece150
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/1946468
Commit-Queue: Paul Lewis <aerotwist@chromium.org>
Reviewed-by: Tim van der Lippe <tvanderlippe@chromium.org>
2019-12-02 14:54:54 +00:00

1.3 KiB

debuglog - backport of util.debuglog() from node v0.11

To facilitate using the util.debuglog() function that will be available when node v0.12 is released now, this is a copy extracted from the source.

require('debuglog')

Return util.debuglog, if it exists, otherwise it will return an internal copy of the implementation from node v0.11.

debuglog(section)

  • section {String} The section of the program to be debugged
  • Returns: {Function} The logging function

This is used to create a function which conditionally writes to stderr based on the existence of a NODE_DEBUG environment variable. If the section name appears in that environment variable, then the returned function will be similar to console.error(). If not, then the returned function is a no-op.

For example:

var debuglog = util.debuglog('foo');

var bar = 123;
debuglog('hello from foo [%d]', bar);

If this program is run with NODE_DEBUG=foo in the environment, then it will output something like:

FOO 3245: hello from foo [123]

where 3245 is the process id. If it is not run with that environment variable set, then it will not print anything.

You may separate multiple NODE_DEBUG environment variables with a comma. For example, NODE_DEBUG=fs,net,tls.