Option_1_CopyAndCutLine.py

import sublime, sublime_plugin

class CopyLine():
    """
    A parent class for the CopyLineCommand and CutLineCommand classes.
    """

    def copy_line(self, **kwargs):
        """
        Copies the cursor line, or all the lines which a multi-line selection
        intersects, into the clipboard. It returns the line region that was
        copied or None if no copying was performed.
        """

        sels = self.view.sel()

        # Abort if there is more than one selection.
        if len(sels) != 1:
            sublime.status_message("Use with only one cursor/selection")
            return None

        # The optional "inc_trailing_newline" arg defaults to true.
        inc_trailing_newline = kwargs.get("inc_trailing_newline", True)

        # full_line() and line() both return the region of the whole of all
        # the lines that their region parameter intersects, but full_line()
        # includes the trailing newline (if there is one).

        if inc_trailing_newline:
            line_region = self.view.full_line(sels[0])
        else:
            line_region = self.view.line(sels[0])

        # Abort if there is nothing to copy.
        if line_region.size() < 1:
            return None

        copy_str = self.view.substr(line_region)
        sublime.set_clipboard(copy_str)

        return line_region


class CopyLineCommand(sublime_plugin.TextCommand, CopyLine):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard.
    """

    def run(self, edit, **kwargs):

        line_region = self.copy_line(**kwargs)

        if line_region is None:
            return

        num_chars = line_region.size()

        if num_chars == 1: char_word = "character"
        else:              char_word = "characters"

        msg = "Copied %d %s" % (num_chars, char_word)
        sublime.status_message(msg)


class CutLineCommand(sublime_plugin.TextCommand, CopyLine):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard
    and deletes the line.
    """

    def run(self, edit, **kwargs):

        line_region = self.copy_line(**kwargs)

        if line_region is None:
            return

        self.view.erase(edit, line_region)

        num_chars = line_region.size()

        if num_chars == 1: char_word = "character"
        else:              char_word = "characters"

        msg = "Cut %d %s" % (num_chars, char_word)
        sublime.status_message(msg)

Option_2_CopyAndCutLine.py

import sublime, sublime_plugin

class CopyLine(sublime_plugin.TextCommand):
    """
    A parent class for the CopyLineCommand and CutLineCommand classes.
    """

    def copy_line(self, **kwargs):
        """
        Copies the cursor line, or all the lines which a multi-line selection
        intersects, into the clipboard. It returns the line region that was
        copied or None if no copying was performed.
        """

        sels = self.view.sel()

        # Abort if there is more than one selection.
        if len(sels) != 1:
            sublime.status_message("Use with only one cursor/selection")
            return None

        # The optional "inc_trailing_newline" arg defaults to true.
        inc_trailing_newline = kwargs.get("inc_trailing_newline", True)

        # full_line() and line() both return the region of the whole of all
        # the lines that their region parameter intersects, but full_line()
        # includes the trailing newline (if there is one).

        if inc_trailing_newline:
            line_region = self.view.full_line(sels[0])
        else:
            line_region = self.view.line(sels[0])

        # Abort if there is nothing to copy.
        if line_region.size() < 1:
            return None

        copy_str = self.view.substr(line_region)
        sublime.set_clipboard(copy_str)

        return line_region


class CopyLineCommand(CopyLine):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard.
    """

    def run(self, edit, **kwargs):

        line_region = self.copy_line(**kwargs)

        if line_region is None:
            return

        num_chars = line_region.size()

        if num_chars == 1: char_word = "character"
        else:              char_word = "characters"

        msg = "Copied %d %s" % (num_chars, char_word)
        sublime.status_message(msg)


class CutLineCommand(CopyLine):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard
    and deletes the line.
    """

    def run(self, edit, **kwargs):

        line_region = self.copy_line(**kwargs)

        if line_region is None:
            return

        self.view.erase(edit, line_region)

        num_chars = line_region.size()

        if num_chars == 1: char_word = "character"
        else:              char_word = "characters"

        msg = "Cut %d %s" % (num_chars, char_word)
        sublime.status_message(msg)

Option_3_CopyAndCutLine.py

import sublime, sublime_plugin

def copy_line(view, **kwargs):
    """
    Copies either the cursor line, or all the lines that a multi-line selection
    intersects, into the clipboard. It returns the line region which was copied
    or None if no copying was performed.
    """

    sels = view.sel()

    # Abort if there is more than one selection.
    if len(sels) != 1:
        sublime.status_message("Use with only one cursor/selection")
        return None

    # The "inc_trailing_newline" arg defaults to true.
    inc_trailing_newline = kwargs.get("inc_trailing_newline", True)

    if inc_trailing_newline:
        # All lines the region intersects plus trailing newline (if any).
        line_region = view.full_line(sels[0])
    else:
        # All lines the region intersects but not a trailing newline.
        line_region = view.line(sels[0])

    copy_str = view.substr(line_region)
    copy_str_len = len(copy_str)

    # Abort if there is no text to copy.
    if copy_str_len == 0 or (copy_str_len == 1 and copy_str[0] == "\n"):
        sublime.status_message("The line is blank")
        return None

    sublime.set_clipboard(copy_str)

    return line_region


def display_message(line_region, cut_line):
    """
    Displays the copy or cut status message.
    """

    num_chars = line_region.size()

    if cut_line: copy_or_cut_word = "Cut"
    else:        copy_or_cut_word = "Copied"

    if num_chars == 1: char_word = "character"
    else:              char_word = "characters"

    msg = "%s %d %s" % (copy_or_cut_word, num_chars, char_word)

    sublime.status_message(msg)


class CopyLineCommand(sublime_plugin.TextCommand):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard.
    """

    def run(self, edit, **kwargs):

        line_region = copy_line(self.view, **kwargs)

        if line_region is None:
            return

        cut_line = False
        display_message(line_region, cut_line)


class CutLineCommand(sublime_plugin.TextCommand):
    """
    A Sublime Text plugin which copies the cursor line into the clipboard
    and deletes the line.
    """

    def run(self, edit, **kwargs):

        line_region = copy_line(self.view, **kwargs)

        if line_region is None:
            return

        self.view.erase(edit, line_region)

        cut_line = True
        display_message(line_region, cut_line)

The 2 code options above are for a StackOverflow question I've made about OO design, both work perfectly well.

EDIT: Implementing r-stein's suggestion in my StackOverflow question led me to option 3 above which is the one to download should anyone want to use the plugin.

In case anyone wants to use this Sublime Text plugin, here's the info.

• Name: Copy And Cut Line
• File: CopyAndCutLine.py
• Requirements: Plugin for Sublime Text v2 and v3
• ST Commands: copy_line, cut_line
• Optional Arg: inc_trailing_newline: boolean (default true)

Description:

This plugin for Sublime Text has been designed so that the cursor line can be copied or cut into the clipboard using a single key binding, without the line being selected first. It provides two commands; "copy_line" and "cut_line". When used with a multi-line selection all of the lines that the selection intersects will be copied or cut. However the commands will abort if there is more than one cursor in use - they are designed to be used to quickly copy or cut a line or group of lines without having to select the exact region and are not intended to be used during advanced multiple selection editing when the benefit of using a single key binding to copy or cut a line is negligible. Both commands can take an optional boolean arg called "inc_trailing_newline" which controls whether to include the trailing newline, this defaults to true.

Example keys:

// Include trailing newlines (the default behaviour):
{ "keys": ["ctrl+shift+c"], "command": "copy_line" },
{ "keys": ["ctrl+shift+x"], "command": "cut_line" },

// Do not include trailing newlines:
{ "keys": ["ctrl+shift+c"], "command": "copy_line", "args": {"inc_trailing_newline": false } },
{ "keys": ["ctrl+shift+x"], "command": "cut_line", "args": {"inc_trailing_newline": false } },

Hope this helps.