Re: Regex extracting string between two words not working

[mronetwo]

Thank you. That works. Could you explain to me what was wrong with my code? It 
seems that the important part is the


var matches: array[1, string]

Run

Why is


var matches: seq[string]

Run

wrong? I thought that's a list of strings that can be dynamically extended.

Re: Regex extracting string between two words not working

[libraM]

With some fixes:


import re, strutils

let buf = """
START
{
  "start_h":10,
  "start_m":40,
  "end_h":11,
  "end_m":40,
  "delta_h":0,
  "delta_m":0,
  "project_ID":0
}
END
"""

var
  dataBuf: string = ""
  buildingRecord: bool

if "START" in buf:
  buildingRecord = true

if buildingRecord:
  dataBuf.add(buf)

if "END" in buf and buildingRecord:
  # Extract the message.
  var matches: array[1, string]
  var matched = find(dataBuf, re(r"START(.+)END", flags={reDotAll}), 
matches)
  
  if matched >= 0:
  # Or just:
  # if contains(dataBuf, re(r"START(.+)END", flags={reDotAll}), matches):
echo(matches[0])


Run

Regex extracting string between two words not working

[mronetwo]

Hello,

I hope it won't be a garbage post, because I'm missing something super simple...

I'm sending a Json from a Python script to a server written in Nim. The Json 
data is between `START` and `END` strings.


if "START" in buf:
  buildingRecord = true

if buildingRecord:
  dataBuf.add(buf)

if "END" in buf and buildingRecord:
  # Extract the message.
  var matches: seq[string]
  var matched = find(dataBuf, re"START((.|\s)*)END", matches)
  
  if matched > 0:
echo(matches[0])

Run

The regex finds no matches. I hope it's not a problem with the regex itself. 
I've tested it online and it seems to work. The Json looks like so:


{
  "start_h":10,
  "start_m":40,
  "end_h":11,
  "end_m":40,
  "delta_h":0,
  "delta_m":0,
  "project_ID":0
}

Run

It gets wrapped between `START` and `END` and pushed through a socket to the 
server. Server gets the data for sure. It just fails to extract the data with 
regex.