perl: reg.expr: combine starting and ending removal in one exprecion Post: 302347757

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Top Forums Shell Programming and Scripting perl: reg.expr: combine starting and ending removal in one exprecion Post 302347757 by alex_5161 on Wednesday 26th of August 2009 10:35:21 AM

08-26-2009

Registered User

perl: reg.expr: combine starting and ending removal in one exprecion

Hello,
I am new in perl and in regular exprecion; so I am looking for help (or an experienced advise.)

The target is a triming spaces from a string: i.e., remove spases from begining and from end of a string.
One of main point of a searched solution is performance: for current task it is very important.
Therefore simple loop character by character seems to me ineffective.
I guess the reg.exp. engine should be pretty sufficient.
So, I've come out with:

Code:

 # $str = "   some text    "
  $str=~s/^[ ]*//;
  $str=~s/[ ]*$//;

This works fine,but,
first of all: I could not combine both patern into one exprecion.
Would you suggest how it could be done?
second: What about time? What expected to be longer : one more complicated regexp or twice, but simple? Who know how that task is processed inside of perl?

And last question: is there simpler way to do such simple task in perl?

alex_5161

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waddstr

addstr(3cur)															      addstr(3cur)

Name
       addstr, waddstr, mvaddstr, mvwaddstr - add string to window

Syntax
       #include <cursesX.h>

       int addstr(str)
       char *str;

       int waddstr(win, str)
       WINDOW *win;
       char *str;

       int mvaddstr(y, x, str)
       int y, x;
       char *str;

       int mvwaddstr(win, y, x, str)
       WINDOW *win;
       int y, x;
       char *str;

Description
       The routine writes all the characters of the null-terminated character string on the default window at the current (y, x) coordinates.

       The routine writes all the characters of the null terminated character string on the specified window at the current (y, x) coordinates.

       The routine writes all the characters of the null terminated character string on the default window at the specified (y, x) coordinates.

       The routine writes all the characters of the null terminated character string on the specified window at the specified (y, x) coordinates.

       The  following  information  applies to all the routines.  All the routines return if writing the string causes illegal scrolling.  In this
       case the routine will write as much as possible of the string on the window.

       These routines are functionally equivalent to calling or once for each character in the string.

       The routines and are macros.

Return Values
       The and functions return OK on success and ERR on error.

See Also
       addch(3cur), waddch(3cur)

																      addstr(3cur)