1 #! /usr/bin/env python

     2 

     3 # Emulate some Perl command line options.

     4 # Usage: pp [-a] [-c] [-d] [-e scriptline] [-F fieldsep] [-n] [-p] [file] ...

     5 # Where the options mean the following:

     6 #   -a            : together with -n or -p, splits each line into list F

     7 #   -c            : check syntax only, do not execute any code

     8 #   -d            : run the script under the debugger, pdb

     9 #   -e scriptline : gives one line of the Python script; may be repeated

    10 #   -F fieldsep   : sets the field separator for the -a option [not in Perl]

    11 #   -n            : runs the script for each line of input

    12 #   -p            : prints the line after the script has run

    13 # When no script lines have been passed, the first file argument

    14 # contains the script.  With -n or -p, the remaining arguments are

    15 # read as input to the script, line by line.  If a file is '-'

    16 # or missing, standard input is read.

    17 

    18 # XXX To do:

    19 # - add -i extension option (change files in place)

    20 # - make a single loop over the files and lines (changes effect of 'break')?

    21 # - add an option to specify the record separator

    22 # - except for -n/-p, run directly from the file if at all possible

    23 

    24 import sys

    25 import string

    26 import getopt

    27 

    28 FS = ''

    29 SCRIPT = []

    30 AFLAG = 0

    31 CFLAG = 0

    32 DFLAG = 0

    33 NFLAG = 0

    34 PFLAG = 0

    35 

    36 try:

    37     optlist, ARGS = getopt.getopt(sys.argv[1:], 'acde:F:np')

    38 except getopt.error, msg:

    39     sys.stderr.write(sys.argv[0] + ': ' + msg + '\n')

    40     sys.exit(2)

    41 

    42 for option, optarg in optlist:

    43     if option == '-a':

    44         AFLAG = 1

    45     elif option == '-c':

    46         CFLAG = 1

    47     elif option == '-d':

    48         DFLAG = 1

    49     elif option == '-e':

    50         for line in string.splitfields(optarg, '\n'):

    51             SCRIPT.append(line)

    52     elif option == '-F':

    53         FS = optarg

    54     elif option == '-n':

    55         NFLAG = 1

    56         PFLAG = 0

    57     elif option == '-p':

    58         NFLAG = 1

    59         PFLAG = 1

    60     else:

    61         print option, 'not recognized???'

    62 

    63 if not ARGS: ARGS.append('-')

    64 

    65 if not SCRIPT:

    66     if ARGS[0] == '-':

    67         fp = sys.stdin

    68     else:

    69         fp = open(ARGS[0], 'r')

    70     while 1:

    71         line = fp.readline()

    72         if not line: break

    73         SCRIPT.append(line[:-1])

    74     del fp

    75     del ARGS[0]

    76     if not ARGS: ARGS.append('-')

    77 

    78 if CFLAG:

    79     prologue = ['if 0:']

    80     epilogue = []

    81 elif NFLAG:

    82     # Note that it is on purpose that AFLAG and PFLAG are

    83     # tested dynamically each time through the loop

    84     prologue = [ \

    85             'LINECOUNT = 0', \

    86             'for FILE in ARGS:', \

    87             '   \tif FILE == \'-\':', \

    88             '   \t   \tFP = sys.stdin', \

    89             '   \telse:', \

    90             '   \t   \tFP = open(FILE, \'r\')', \

    91             '   \tLINENO = 0', \

    92             '   \twhile 1:', \

    93             '   \t   \tLINE = FP.readline()', \

    94             '   \t   \tif not LINE: break', \

    95             '   \t   \tLINENO = LINENO + 1', \

    96             '   \t   \tLINECOUNT = LINECOUNT + 1', \

    97             '   \t   \tL = LINE[:-1]', \

    98             '   \t   \taflag = AFLAG', \

    99             '   \t   \tif aflag:', \

   100             '   \t   \t   \tif FS: F = string.splitfields(L, FS)', \

   101             '   \t   \t   \telse: F = string.split(L)' \

   102             ]

   103     epilogue = [ \

   104             '   \t   \tif not PFLAG: continue', \

   105             '   \t   \tif aflag:', \

   106             '   \t   \t   \tif FS: print string.joinfields(F, FS)', \

   107             '   \t   \t   \telse: print string.join(F)', \

   108             '   \t   \telse: print L', \

   109             ]

   110 else:

   111     prologue = ['if 1:']

   112     epilogue = []

   113 

   114 # Note that we indent using tabs only, so that any indentation style

   115 # used in 'command' will come out right after re-indentation.

   116 

   117 program = string.joinfields(prologue, '\n') + '\n'

   118 for line in SCRIPT:

   119     program = program + ('   \t   \t' + line + '\n')

   120 program = program + (string.joinfields(epilogue, '\n') + '\n')

   121 

   122 import tempfile

   123 fp = tempfile.NamedTemporaryFile()

   124 fp.write(program)

   125 fp.flush()

   126 if DFLAG:

   127     import pdb

   128     pdb.run('execfile(%r)' % (tfn,))

   129 else:

   130     execfile(tfn)