Substring a String value

[abhishekrongali]

Hi,

Can we substring a string based on size?

Example:

1. let a = "123456678" -> I want to split this value based on size and needed first 4 characters only
   Expected value = "1234"

[catull]

@abhishekrongali Have you already consulted this page ?

@larsga

I have tried to come up with some approaches.

I have this input

{
  "s": "1234567890"
}

This is the transformation.

{
  "s": .s,
  "capture": capture (.s, "^(?<first>.{4})(?<rest>.*)$"),
  "first": .capture.first,
  "replace": replace (.s, "^(.{4}).*$", "$1")
}

And this is the result:

{
  "s" : "1234567890",
  "capture" : {
    "first" : "1234",
    "rest" : "567890"
  },
  "first" : "1234",
  "replace" : "$1"
}

Now, unless I am doing something wrong, the replace method should allow for regexp references, similar to the capture case.
I have tried with "%0", "_0", "$0", as well as "%1", "_1", "$1", and a few other; none of them work.

It should work, see this online example I created quickly.

[abhishekrongali]

Thank you, works perfectly! :)