Execute Python from within current file

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created 2003 · complexity intermediate · author Steve Halpin · version 6.0

---

Inspired by VimTip608.

To execute Python from a range within the current text file and write the output to that file (replacing the Python), add the snippet below to vimrc (or other suitable *rc file).

Requires a 'proper' Python setup so that the imported modules can be found.

I find it a handy intermediate step between using the Python interpreter on command line and running a complete script. Can be used for easy buffer manipulation, filtering input, preprocessing text and templating-like tasks.

python << EOL
import vim, StringIO,sys
def PyExecReplace(line1,line2):
  r = vim.current.buffer.range(int(line1),int(line2))
  redirected = StringIO.StringIO()
  sys.stdout = redirected
  exec('\n'.join(r) + '\n')
  sys.stdout = sys.__stdout__
  output = redirected.getvalue().split('\n')
  r[:] = output[:-1] # the -1 is to remove the final blank line
  redirected.close()
EOL
command -range Pyer python PyExecReplace(<f-line1>,<f-line2>)

Some examples of use

Simple

print 2 + 2

:Pyer

With the cursor on the 'print' line, that line is replaced with 4.

Filter

for line in vim.current.buffer:
 if line[0] != '\t':
  print line

:%Pyer

Filters out lines beginning with a tab in the current buffer.

Inserting time

import time
print time.ctime()

:%Pyer

Replaces line with date/time.

Getting web content without tags

import urllib2,htmllib,formatter
h = htmllib.HTMLParser(formatter.AbstractFormatter(formatter.DumbWriter()))
h.feed(urllib2.urlopen('http://www.somesite.com').read())

:%Pyer

Inserts the web page text, but not the html tags, for a given site.

Comments

I use the following:

"in vimrc:
"python extensions
py from vim import buffers, windows, command, current, error
py import vim, sys
py from vimpy import *

command! PyExecBuffer py exec('\n'.join(current.buffer))

map <F5> :PyExecBuffer<CR>
imap <F5> <Esc><F5><CR>a

vimpy.py

import sys, vim
class Buffer:
    def __init__(self,buf):
        self.buf=buf
    def write(self,s):
        ll=s.split('\n')
        self.buf[-1]+=ll[0]
        for l in ll[1:]:
            self.buf.append(l)
    def clear(self):
        del self.buf[:]

def redirect(buf=None):
    buf = buf or vim.current.window.buffer
    try:
        sys._stdout
    except:
        sys._stdout=sys.stdout
    sys.stdout = Buffer(buf)

Then I start Vim, create new window (<C-W> N), and do

:py redirect(current.window.buffer)

on a window I want to receive all printed data.

Then <F5> in any buffer executes the buffer contents in Python, output goes to the window selected.

To redirect output back just do sys.stdout = sys._stdout

Simpler version

This does not require python support in vim. Select lines using V and then press F5.

:vnoremap <f5> :!python<CR>

source.

This one saves the current file before execution and does come back without PAUSE (tested in windows)

noremap <F5> <ESC>:w<CR>:silent execute "!python %"<CR><CR>

Run Python samples from Vim

----
" >>> Play Python from within gVim
" >>> useful to copy/paste samples and run inside Vim
" >>> [usage] Normal_<C-P> against a Python block
" >>>         Visual_<C-P> on Visual Python block
" >>>         Insert_<C-P>, automatically add print()
" ================================
if has('python') || has('python3')
" ================================
nn<silent>z_ :let @/=@_<CR>
nn<silent>Zz :let pyf=tempname()<CR>
   \:sil!let python=has('python3')?'py3file ':'pyfile '<CR>
   \:sil!let yank = substitute(@0,'[>.]\{3}\s\=','','g')<CR>
   \:sil!call writefile(split(yank,'\n'),pyf)<CR>
   \:sil!redir @"<Bar>sil!exe 'silent!'.python.pyf<CR>:redir END<CR>p
nm<silent> <C-P>   yip}Zz
xm<silent> <C-P> :y<CR>Zz
im<silent> <C-P> <Esc>:s/\([>.]\{3}\s\=\)\=\(.*\)/\1print(\2)<CR>z_<C-P>
" --------------------------------------------
endif


# example insert mode, as calculator, <C-P>
1/2

# example <C-P> anywhere inside block
help(help)

# example <C-P> anywhere inside block
>>> # Fibonacci series:
... # the sum of two elements defines the next
... a, b = 0, 1
>>> while b < 10:
...     print(b)
...     a, b = b, a+b
...

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