Put ligatures where possible. Save characters.

ligaturify.py

#/usr/bin/python3
# -*- coding: utf-8 -*-
import sys

if sys.version_info < (3,):
  raise Exception("This requires Python 3 to run. Sorry.")

ligatures = {	"db": "ȸ",
	"AE":	"Æ",
	"ae":	"æ",
	"OE":	"Œ",
	"oe":	"œ",	
	"ue":	"ᵫ",
	"ff":	"ff",
	"IJ":	"IJ",
	"ij":	"ij",
	"fi":	"fi",
	"fl":	"fl",
	"ffi":	"ffi",
	"ffi":	"ffi",
	"ffi":	"ffi",
	"ffl":	"ffl",
	"ffi":	"ffl",
	"ffl":	"ffl",
	"ffl":	"ffl",
	"ft":	"ſt",
	"OI":	"Ƣ",
	"oi":	"ƣ",
	"IJ":	"IJ",
	"ij":	"ij",
	"qp":	"ȹ",
	"st":	"st",
	}

additional_ligatures = {	"et": "&",
	"SS":	"ẞ",
	"ss":	"ß",
	}

digraphs = {	"DZ":	"DZ",
	"Dz":	"Dz",
	"dz":	"dz",
	"DŽ":	"DŽ",
	"Dž":	"Dž",
	"dž":	"dž",
	"LJ":	"LJ",
	"Lj":	"Lj",
	"lj":	"lj",
	"NJ":	"NJ",
	"Nj":	"Nj",
	"nj":	"nj",
	}


text = sys.stdin.read()

for replacement_list in [ligatures, digraphs]:
  for letters, replacement in replacement_list.items():
    text = text.replace(letters, replacement)

sys.stdout.write(text)

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