Difference between console.log and sys.puts in node.js?

Question

In node.js you can use console.log or sys.puts to print out to the screen.

What is the preferred method and what is the difference between these?

score 61 · Accepted Answer · edited Jul 24 '11 at 20:38

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sys.puts simply prints the given string in the logs.

But if you want to print a more complex object (Array, JSON, JSObject) you have to use console.log because you want to "look inside" of the object.

sys.puts would give you only "[object object]" for example.

edited Jul 24 '11 at 20:38

Alberto Zaccagni

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answered Oct 11 '10 at 07:45

Elias

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yes, however you don't HAVE to use console logs to see the object. sys.puts("check out this funky object in detail: " + sys.inspect(yourobject)); – fullstacklife Oct 19 '10 at 15:20

score 16 · Answer 2 · edited Oct 05 '15 at 11:01

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Both just write to the stdout stream. The difference is that sys.puts just toString's the first argument, and console.log takes multiple arguments, and will sys.inspect the first arg if it's not a string.

edited Oct 05 '15 at 11:01

Philipp Kyeck

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answered Oct 11 '10 at 21:19

isaacs

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`sys.inspect` is now `util.inspect` – 700 Software Jul 25 '11 at 12:45
Actually console is used to print to stdout and stderr streams. – Mikhail.Mamaev Nov 28 '11 at 12:57

score 9 · Answer 3 · answered Apr 22 '11 at 02:23

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Puts is deprecated in since version 0.2.3

answered Apr 22 '11 at 02:23

angry kiwi

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Please cite the source by linking to where you found the information. – 700 Software Apr 28 '11 at 18:47
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Speaking of deprecation, it looks like the 'sys' module has become the 'util' module. The puts() method is still around, but the utils.p() prints a deprecated warning. – xer0x May 06 '11 at 05:06
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@xer0x : 'sys' module was renamed to be 'util'. It was a Fix on require('sys') #3577 – Amol M Kulkarni Jan 17 '13 at 09:39

score 3 · Answer 4 · answered Oct 15 '10 at 17:03

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Also you can use console.log without requiring the sys module.

answered Oct 15 '10 at 17:03

daralthus

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score 2 · Answer 5 · answered Oct 10 '11 at 07:52

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console.dir(objectToInspect)

This might be another way to inspect objects.

answered Oct 10 '11 at 07:52

Rajkamal Subramanian

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score 1 · Answer 6 · answered Jan 17 '13 at 09:35

sys.puts([...]);

Is a synchronous output function. Simply it is a blocking function as in Node.js language.

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

Prints to stdout with newline.

For more Info:

http://nodejs.org/api/stdio.html#stdio_console_log_data

http://nodejs.org/api/util.html#util_util_puts

Note: 'sys' module was renamed to be 'util' (Supported by link) It was a Fix #3577

score 0 · Answer 7 · answered Oct 31 '20 at 03:28

The preferred method is console.log(). sys.puts() has been removed.

The sys module was renamed util with this commit dated Oct 12, 2010. So sys.puts() became util.puts(). util.puts() was added in v0.3.0, deprecation since v0.11.3, and removed in v12.0.0. The documentation advises to use console.log() instead.

Difference between console.log and sys.puts in node.js?

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