• If you run

  tmpl = "This is the first line\n And this is the second line"
  print("tmpl)
  

  you get

   This is the first line
   And this is the second line
  

  So you get a new line expanded.

• But if you write in a file, you will not get that:

  Put in test.tmpl:

  This is the first line\n And this is the second line
  

  and run

  with open("test.tmpl") as f:
      contents = f.read()
      print(contents)
  

  you get

  This is the first line\n And this is the second line
  

Why this behaviour? How can you get the the contents displays the same than tmpl?

CodePudding user response：

A Python string is interpreted by the Python interpreter. The Python interpreter knows what escape characters are and how to deal with them.

When reading a text file, you get the characters as they are. A newline in a text file consists of the characters 0x0D (CR; carriage return) and/or 0x0A (LF; line feed). You get that when pressing Enter on your keyboard. If you want to consider escape characters in a text file, you need to implement that yourself.

Applied to your case:

with open("test.tmpl") as f:
    contents = f.read()
    contents = bytes(contents, "utf-8").decode("unicode_escape")
    print(contents)