Almost totally rewritten.

Demo/scripts/pp.py

 #! /usr/local/python
 
-# Wrapper around Python to emulate the Perl -ae options:
-# (1) first argument is a Python command
-# (2) rest of arguments are input to the command in an implied loop
-# (3) each line is put into the string L with trailing '\n' stripped
-# (4) the fields of the line are put in the list F
-# (5) also: FILE: full filename; LINE: full line; FP: open file object
-# The command line option "-f FS" sets the field separator;
-# this is available to the program as FS.
+# Emulate some Perl command line options.
+# Usage: pp [-a] [-c] [-d] [-e scriptline] [-F fieldsep] [-n] [-p] [file] ...
+# Where the options mean the following:
+#   -a            : together with -n or -p, splits each line into list F
+#   -c            : check syntax only, do not execute any code
+#   -d            : run the script under the debugger, pdb
+#   -e scriptline : gives one line of the Python script; may be repeated
+#   -F fieldsep   : sets the field separator for the -a option [not in Perl]
+#   -n            : runs the script for each line of input
+#   -p            : prints the line after the script has run
+# When no script lines have been passed, the first file argument
+# contains the script.  With -n or -p, the remaining arguments are
+# read as input to the script, line by line.  If a file is '-'
+# or missing, standard input is read.
+
+# XXX To do:
+# - add -i extension option (change files in place)
+# - make a single loop over the files and lines (changes effect of 'break')?
+# - add an option to specify the record separator
+# - except for -n/-p, run directly from the file if at all possible
 
 import sys
 import string
 import getopt
 
 FS = ''
+SCRIPT = []
+AFLAG = 0
+CFLAG = 0
+DFLAG = 0
+NFLAG = 0
+PFLAG = 0
+
+try:
+	optlist, ARGS = getopt.getopt(sys.argv[1:], 'acde:F:np')
+except getopt.error, msg:
+	sys.stderr.write(sys.argv[0] + ': ' + msg + '\n')
+	sys.exit(2)
 
-optlist, args = getopt.getopt(sys.argv[1:], 'f:')
 for option, optarg in optlist:
-	if option == '-f': FS = optarg
-
-command = args[0]
-
-if not args[1:]: args.append('-')
-
-prologue = [ \
-	'for FILE in args[1:]:', \
-	'\tif FILE == \'-\':', \
-	'\t\tFP = sys.stdin', \
-	'\telse:', \
-	'\t\tFP = open(FILE, \'r\')', \
-	'\twhile 1:', \
-	'\t\tLINE = FP.readline()', \
-	'\t\tif not LINE: break', \
-	'\t\tL = LINE[:-1]', \
-	'\t\tif FS: F = string.splitfields(L, FS)', \
-	'\t\telse: F = string.split(L)' \
+	if option == '-a':
+		AFLAG = 1
+	elif option == '-c':
+		CFLAG = 1
+	elif option == '-d':
+		DFLAG = 1
+	elif option == '-e':
+		for line in string.splitfields(optarg, '\n'):
+			SCRIPT.append(line)
+	elif option == '-F':
+		FS = optarg
+	elif option == '-n':
+		NFLAG = 1
+		PFLAG = 0
+	elif option == '-p':
+		NFLAG = 1
+		PFLAG = 1
+	else:
+		print option, 'not recognized???'
+
+if not ARGS: ARGS.append('-')
+
+if not SCRIPT:
+	if ARGS[0] == '-':
+		fp = sys.stdin
+	else:
+		fp = open(ARGS[0], 'r')
+	while 1:
+		line = fp.readline()
+		if not line: break
+		SCRIPT.append(line[:-1])
+	del fp
+	del ARGS[0]
+	if not ARGS: ARGS.append('-')
+
+if CFLAG:
+	prologue = ['if 0:']
+	epilogue = []
+elif NFLAG:
+	# Note that it is on purpose that AFLAG and PFLAG are
+	# tested dynamically each time through the loop
+	prologue = [ \
+		'LINECOUNT = 0', \
+		'for FILE in ARGS:', \
+		'   \tif FILE == \'-\':', \
+		'   \t   \tFP = sys.stdin', \
+		'   \telse:', \
+		'   \t   \tFP = open(FILE, \'r\')', \
+		'   \tLINENO = 0', \
+		'   \twhile 1:', \
+		'   \t   \tLINE = FP.readline()', \
+		'   \t   \tif not LINE: break', \
+		'   \t   \tLINENO = LINENO + 1', \
+		'   \t   \tLINECOUNT = LINECOUNT + 1', \
+		'   \t   \tL = LINE[:-1]', \
+		'   \t   \taflag = AFLAG', \
+		'   \t   \tif aflag:', \
+		'   \t   \t   \tif FS: F = string.splitfields(L, FS)', \
+		'   \t   \t   \telse: F = string.split(L)' \
+		]
+	epilogue = [ \
+		'   \t   \tif not PFLAG: continue', \
+		'   \t   \tif aflag:', \
+		'   \t   \t   \tif FS: print string.joinfields(F, FS)', \
+		'   \t   \t   \telse: print string.join(F)', \
+		'   \t   \telse: print L', \
 		]
+else:
+	prologue = ['if 1:']
+	epilogue = []
 
 # Note that we indent using tabs only, so that any indentation style
 # used in 'command' will come out right after re-indentation.
 
-program = string.joinfields(prologue, '\n')
-for line in string.splitfields(command, '\n'):
-	program = program + ('\n\t\t' + line)
-program = program + '\n'
+program = string.joinfields(prologue, '\n') + '\n'
+for line in SCRIPT:
+	program = program + ('   \t   \t' + line + '\n')
+program = program + (string.joinfields(epilogue, '\n') + '\n')
 
-exec(program)
+import tempfile
+tfn = tempfile.mktemp()
+try:
+	fp = open(tfn, 'w')
+	fp.write(program)
+	fp.close()
+	if DFLAG:
+		import pdb
+		pdb.run('execfile(' + `tfn` + ')')
+	else:
+		execfile(tfn)
+finally:
+	import os
+	try:
+		os.unlink(tfn)
+	except:
+		pass