How to Read a File Without Newlines

How to read a file without newlines?

You can read the whole file and split lines using str.splitlines:

temp = file.read().splitlines()

Or you can strip the newline by hand:

temp = [line[:-1] for line in file]

Note: this last solution only works if the file ends with a newline, otherwise the last line will lose a character.

This assumption is true in most cases (especially for files created by text editors, which often do add an ending newline anyway).

If you want to avoid this you can add a newline at the end of file:

with open(the_file, 'r+') as f:
    f.seek(-1, 2)  # go at the end of the file
    if f.read(1) != '\n':
        # add missing newline if not already present
        f.write('\n')
        f.flush()
        f.seek(0)
    lines = [line[:-1] for line in f]

Or a simpler alternative is to strip the newline instead:

[line.rstrip('\n') for line in file]

Or even, although pretty unreadable:

[line[:-(line[-1] == '\n') or len(line)+1] for line in file]

Which exploits the fact that the return value of or isn't a boolean, but the object that was evaluated true or false.

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The readlines method is actually equivalent to:

def readlines(self):
    lines = []
    for line in iter(self.readline, ''):
        lines.append(line)
    return lines

# or equivalently

def readlines(self):
    lines = []
    while True:
        line = self.readline()
        if not line:
            break
        lines.append(line)
    return lines

Since readline() keeps the newline also readlines() keeps it.

Note: for symmetry to readlines() the writelines() method does not add ending newlines, so f2.writelines(f.readlines()) produces an exact copy of f in f2.

Reading a file into variable without newlines

You can do search/replace in bash after reading file content:

options=$(<vm.options)
# replace \n with space
options="${options//$'\n'/ }"

Now examine options variable:

declare -p options

declare -- options="-Random 1 -Letters2 -Occur 3 -In -Passwords9"

How to read .txt file without .readlines() / replace UTF-8 newline character with \n?

Your file already contains newlines ('\x0a' is an escape for the exact same character that '\n' produces). I'm assuming your renderer is sending out HTML though, and HTML doesn't care about newlines in the text (outside of pre blocks, and other blocks styled similarly).

So either wrap the data in a pre block, or replace the '\n' with <br> tags (which are how HTML says "No, really, I want a line break"), e.g.:

from_text = from_text.replace("\n", "<br>\n")

Leaving in the newlines may be handy to people viewing the source, so I replaced with both the <br> tag and a newline (Python won't replace in a replacement, so don't worry about infinite replacement just because the newline was part of the replacement).

to read line from file without getting "\n" appended at the end

To remove just the newline at the end:

line = line.rstrip('\n')

The reason readline keeps the newline character is so you can distinguish between an empty line (has the newline) and the end of the file (empty string).

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