An awk script to extract source code blocks from Markdown files

By Alvin Alexander. Last updated: January 5, 2021

I just wrote this awk script to extract all of the Scala source code examples out of a Markdown file. It can easily be converted to extract all of the source code examples out of an Asciidoc file, which is something else I will do with it eventually.

Here’s the awk script:

BEGIN {
    # awk doesn’t have true/false variables, so
    # create our own, and initialize our variable.
    true = 1
    false = 0
    printLine = false
}

{
    # look for ```scala to start a block and ``` to stop a block.
    # `[:space:]*` that is used below means “zero or more spaces”.
    if ($0 ~ /^```scala/) {
        printLine = true
        print ""
    } else if ($0 ~ /^```[:space:]*$/) {
        # if printLine was true, we were in a ```scala block,
        # so print the end matter, then make printLine false
        # so printing will stop
        if (printLine == true) {
            print "```"
        }
        printLine = false
    }
 
    if (printLine) print $0
}

linux-unix

awk

block

extract

file

An awk script to extract source code blocks from Markdown files

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