console Node.js v0.8.26 Manual & Documentation

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# console#

    Stability: 4 - API Frozen

- {Object}

For printing to stdout and stderr. Similar to the console object functions provided by most web browsers, here the output is sent to stdout or stderr.

## console.log([data], [...])#

Prints to stdout with newline. This function can take multiple arguments in a `printf()`-like way. Example:

    console.log('count: %d', count);

If formatting elements are not found in the first string then `util.inspect` is used on each argument. See util.format() for more information.

## console.info([data], [...])#

Same as `console.log`.

## console.error([data], [...])#

Same as `console.log` but prints to stderr.

## console.warn([data], [...])#

Same as `console.error`.

## console.dir(obj)#

Uses `util.inspect` on `obj` and prints resulting string to stdout.

## console.time(label)#

Mark a time.

## console.timeEnd(label)#

Finish timer, record output. Example:

    console.time('100-elements');
    for (var i = 0; i < 100; i++) {
      ;
    }
    console.timeEnd('100-elements');

## console.trace(label)#

Print a stack trace to stderr of the current position.

## console.assert(expression, [message])#

Same as assert.ok() where if the `expression` evaluates as `false` throw an AssertionError with `message`.