Add Line Numbers to Log Output

Feb 5, 2017 · 89 words · 1 minute read

#debug #example #flags #line #log #logging #numbers #output

Many programming languages allow you to print the line number of when and where something has happened. This is very useful for debugging a problem when it has occurred. By default in Go this is off, but you can turn it on when logging by setting flags.

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package main

import "log"

func main() {

    // Enable line numbers in logging
    log.SetFlags(log.LstdFlags | log.Lshortfile)

    // Will print: "[date] [time] [filename]:[line]: [text]"
    log.Println("Logging w/ line numbers on golangcode.com")
}

logging in golang with line numbers

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Author: Edd Turtle

Edd is the Lead Developer at Hoowla, a prop-tech startup, where he spends much of his time working on production-ready Go and PHP code. He loves coding, but also enjoys cycling and camping in his spare time.

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