how to console.log the number of the line in the code

Question

how to console.log the line number of the called function or console.log()

for example in the IDE i can see the line like this. how can I show that by console.log it

14 
15 // other code/logic
16
17 console.error(`error at line ${herePutTheLogic}`);
18

output: error at line 17

Does this answer your question? [A proper wrapper for console.log with correct line number?](https://stackoverflow.com/questions/13815640/a-proper-wrapper-for-console-log-with-correct-line-number) — Ethicist, Sep 13 '22 at 15:07
If you're coding into VSCode, [Turbo Console Log](https://marketplace.visualstudio.com/items?itemName=ChakrounAnas.turbo-console-log) might be right choice if you don't want to go deep into creating your own solution for it! — Mr.Online, Sep 13 '22 at 15:09
Similar question https://stackoverflow.com/questions/1340872/how-to-get-javascript-caller-function-line-number-and-caller-source-url — Peterrabbit, Sep 13 '22 at 15:09

score 3 · Accepted Answer · edited Sep 13 '22 at 15:20

3

You can use (new Error()).stack to get the stack trace at the current line. it would require some additional parsing to get the line number however.

e.g., console.log((new Error()).stack.split(':')[1]) will get it assuming it is at the root of the file, but once you start adding it to functions you'd need something a little more sophisticated.

console.log(
  "❌ the error is on the line N." +
  new Error().stack.split(":")[3]
);

edited Sep 13 '22 at 15:20

Laaouatni Anas

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answered Sep 13 '22 at 15:10

JaredMcAteer

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it give me `//stacksnippets.net/js` as output here on stack – stackdeveloper Sep 13 '22 at 15:12
Looks like you have a URL in your stack trace, you need to account for that in your index choice – JaredMcAteer Sep 13 '22 at 15:13
ok I will try with localhost and tell you if is working, I upvoted in the main time – stackdeveloper Sep 13 '22 at 15:13
2

My example is very brittle, you will need to customize the parsing done for your use case. try console logging without the split and you will see the line numb/column at the end of each file URI – JaredMcAteer Sep 13 '22 at 15:15
1

I saw now someone edited your answer, and is super correct now (with also code snippet), thanks – stackdeveloper Sep 13 '22 at 15:23

how to console.log the number of the line in the code

1 Answers1