old_contents: from flask import render_template, jsonify, request
  from app import app
  from app import evolver
  
  
  @app.route('/')
  @app.route('/index')
  def index():
      return render_template('index.html')
  
  
  def format_transcriptions(transcriptions):
      '''Split the raw string of transcriptions into
      the correct tuple rules.'''
      return [(pair.split(':')[0], pair.split(':')[1]) for pair in transcriptions.split('\n')]
  
  
  @app.route('/evolve', methods=['POST'])
  def evolve():
      words = request.form['words'].split()
  
      try:
          transcriptions = format_transcriptions(request.form['transcriptions'])
      except IndexError:
          return jsonify({'error': 'Error: Transcription seperator must be a colon'})
  
      try:
          generations = int(request.form['generations'])
      except ValueError:
          return jsonify({'error': 'Error: Generations must be an integer'})
  
      words, rules = evolver.evolve(words, generations, transcriptions)
  
      return jsonify({'rules': rules, 'words': words, 'error': 0})
  
new_contents: from flask import render_template, jsonify, request
  from app import app
  from app import evolver
  
  
  @app.route('/')
  @app.route('/index')
  def index():
      return render_template('index.html')
  
  
  def format_transcriptions(transcriptions):
      '''Split the raw string of transcriptions into
      the correct tuple rules.'''
      clean_transcriptions = transcriptions.strip().lower()
  
      if len(clean_transcriptions) == 0:
          return []
      else:
          return [(pair.split(':')[0], pair.split(':')[1]) for pair in clean_transcriptions.split('\n')]
  
  
  @app.route('/evolve', methods=['POST'])
  def evolve():
      words = request.form['words'].split()
  
      try:
          transcriptions = format_transcriptions(request.form['transcriptions'])
      except IndexError:
          return jsonify({'error': 'Error: Transcription seperator must be a colon'})
  
      try:
          generations = int(request.form['generations'])
      except ValueError:
          return jsonify({'error': 'Error: Generations must be an integer'})
  
      words, rules = evolver.evolve(words, generations, transcriptions)
  
      return jsonify({'rules': rules, 'words': words, 'error': 0})
  
subject: Fix bug when transcriptions are empty