"Pankaj" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > > I have something like below in perl and i am searching for equivalent > in python: > > ::: Perl ::: > *********** > while( <FILEHANDLE> ) > { > > line = $_; > > pattern = "printf\( \"$lineNo \" \),"; > > line =~ s/"for(.*)\((*.)\;(.*)/for$1\($pattern$2\;$3/g; > } > > This is used to > > search for : for ( i = 0; i < 10; i++) > Replace with: for( printf( "10" ), i =0; i < 10; i++) > Where 10 is the line no. >
Here is a solution using pyparsing instead of re's. You're already used to re's from using Perl, so you may be more comfortable using that tool in Python as well. But pyparsing has some builtin features for pattern matching, calling out to callback routines during parsing, and a lineno function to report the current line number, all wrapped up in a simple transformString method call. Download pyparsing at http://pyparsing.sourceforge.net. -- Paul from pyparsing import Keyword,SkipTo,lineno,cStyleComment # define grammar for a for statement for_ = Keyword("for") forInitializer = SkipTo(';').setResultsName("initializer") forStmt = for_ + "(" + forInitializer + ';' # ignore silly comments forStmt.ignore(cStyleComment) # setup a parse action that will insert line numbers # parse actions are all called with 3 args: # - the original string being parsed # - the current parse location where the match occurred # - the matching tokens # if a value is returned from this function, transformString will # insert it in place of the original content def insertPrintStatement(st,loc,toks): lineNumber = lineno(loc,st) if toks[0]: return r'print("%d\n"), %s' % (lineNumber,toks[0]) else: return r'print("%d\n")' % lineNumber forInitializer.setParseAction(insertPrintStatement) # transform some code # this is how you would read in a whole file as a single string #testdata = file(inputfilename).read() # to read the entire file into a list of strings, do: #testdata = file(inputfilename).readlines() # for now, just fake some source code testData = """ for(i = 0; i <= 100; ++i) { /* some stuff */ } for (;;;) { /* do this forever */ } /* this for has been commented out for(a = -1; a < 0; a++) */ """ # use the grammar and the associated parse action to # transform the source code print forStmt.transformString(testData) -------------------------- Gives: for(print("2\n"), i = 0; i <= 100; ++i) { /* some stuff */ } for(print("7\n");;;) { /* do this forever */ } /* this for has been commented out for(a = -1; a < 0; a++) */ -- http://mail.python.org/mailman/listinfo/python-list
