rrunner.py

import sys, io, os
from tempfile import mkstemp

try:
    from IPython.lib.irunner import InteractiveRunner
except ImportError:
    from IPython.irunner import InteractiveRunner

class RRunner(InteractiveRunner):
    """Interactive R runner that has an R_PROFILE
    that specifies an optional prompt and continue
    which is useful to distinguish the prompt from
    R's use of the ">" to mean "greater than" in, i.e.
    "summary.lm".

    The profile can be added to by supplying a
    string or file-like object, to which the call to "options" is appended.
    """

    def __init__(self, program = "R" ,args=None,out=sys.stdout,echo=False,
                 profile='', prompt=">>>R", continue_prompt=">>>+"):
        """New runner."""
        prompt_profile = '\noptions(prompt="%s ", continue="%s ")\n' % (prompt, continue_prompt)

        if type(profile) == type(''):
            profilestr = profile + prompt_profile
        else:
            profilestr = profile.read() + prompt_profile
            
        prompts = [r'%s' % prompt, r'%s' % continue_prompt]
        self.profile = file(mkstemp(suffix='Rprofile')[1], mode='w')
        self.profile.write(profilestr)
        self.profile.close()
        os.environ['R_PROFILE'] = self.profile.name

        self.delaybeforesend = 0.035
        InteractiveRunner.__init__(self,program,prompts,args,out,echo)

        self.child.logfile_send = io.StringIO()#unicode('', 'utf-8'))
        self.child.logfile_read = io.StringIO()#unicode('', 'utf-8'))

        # Run a one-liner to "flush" things a little
        # so the tmp file can be removed.
        # It seems to hang otherwise -- perhaps
        # because the options change the prompts?

        self.echo = False
        self.run_source('flushing...\n')
        os.remove(self.profile.name)
        
    def __del__(self):
        self.child.close()

class EmbeddedRShell:
    def __init__(self):

        self.cout = io.StringIO()
        self.R = RRunner(out=self.cout)
        self.input = u''
        self.output = unicode('', 'utf-8')
        self.log = u''
        self.outlog = file("Rlog",'w')

    def process(self, line, echo=True):

        self.R.run_source('%s\n'% line, get_output=False)
        if echo:
            self.input += '%s\n' % line
        self.log += '%s\n' % line
        
    def flush_input(self):

        v = self.input
        self.input = u''
        return v
    
    def astext(self):

        self.R.child.logfile_read.seek(0)
        s = self.R.child.logfile_read.read()
        
        # R uses fancy quotes in their summaries
        # and so the strings should be interpreted
        # as unicode

        s = s.encode('utf-8').decode('utf-8')
        s = s.replace(self.R.prompts[0], ">")
        s = s.replace(self.R.prompts[1], "+")
        self.R.child.logfile_read.truncate(0)
        return s

shell = EmbeddedRShell()