Hi Folk

I need to write a tricky replacement function.



C = replace A with B in C
C = replace D with E in C

examples of A could be "a cat climbs a tree", examples of B could be
"a dog climbs a alligator". Thereby, I want to make sure that parts
that have already been replaced will not be replaced again (by the E
replaces D statement for example). I will mark all new text (Bs and
Es) with <span class="replacePart">... new text here ....</span>.

How could I go about this? Could I use a regular expression?

Thank you

Nicolaas

..oO(windandwaves)

>I need to write a tricky replacement function.
>
>C = replace A with B in C
>C = replace D with E in C
>
>examples of A could be "a cat climbs a tree", examples of B could be
>"a dog climbs a alligator". Thereby, I want to make sure that parts
>that have already been replaced will not be replaced again (by the E
>replaces D statement for example). I will mark all new text (Bs and
>Es) with <span class="replacePart">... new text here ....</span>.
>
>How could I go about this? Could I use a regular expression?

You could try strtr() first, called with only two parameters. See the
manual for details.

http://www.php.net/strtr

Micha

Unless I am misunderstanding what you are looking for, as I cant see
why this is so complex, why not just use a simple srt_replace
function?

<?php

$find = array('cat','tree');

$replace = array('dog','alligator');

$phrase = "a cat climbs a tree";


echo str_replace($find,$replace,$phrase);

//outputs "a dog climbs a alligator"
?>

> why this is so complex, why not just use a simple srt_replace

that's str_replace

Why is this so hard?

I can do a str_replace. That is easy. However, I do many of them AND
I want to make sure that one replacement does not override another...

e.g.
statement 1 could be: replace "cats" with "dogs"
statement 2 could be: replaced "do" with "did"

as you can see, this could turn "cats" into "didgs"

That is what is the hard part.

Thank you

Nicolaas

windandwaves <nfrancken@gmail.com> wrote in news:1194381953.358772.178700
@q3g2000prf.googlegroups.com:

> Why is this so hard?
>
> I can do a str_replace. That is easy. However, I do many of them AND
> I want to make sure that one replacement does not override another...
>
> e.g.
> statement 1 could be: replace "cats" with "dogs"
> statement 2 could be: replaced "do" with "did"
>
> as you can see, this could turn "cats" into "didgs"
>
> That is what is the hard part.

then yes, go for regex so you can specify beginnings/ends of words as
opposed to characters in a string

..oO(windandwaves)

>Why is this so hard?
>
>I can do a str_replace. That is easy. However, I do many of them AND
>I want to make sure that one replacement does not override another...
>
>e.g.
>statement 1 could be: replace "cats" with "dogs"
>statement 2 could be: replaced "do" with "did"
>
>as you can see, this could turn "cats" into "didgs"
>
>That is what is the hard part.

That's why I suggested to give strtr() a try, which should avoid this
problem.

Micha

On Nov 7, 10:21 am, Michael Fesser <neti...@gmx.de> wrote:
> .oO(windandwaves)
>
> >Why is this so hard?
>
> >I can do a str_replace. That is easy. However, I do many of them AND
> >I want to make sure that one replacement does not override another...
>
> >e.g.
> >statement 1 could be: replace "cats" with "dogs"
> >statement 2 could be: replaced "do" with "did"
>
> >as you can see, this could turn "cats" into "didgs"
>
> >That is what is the hard part.
>
> That's why I suggested to give strtr() a try, which should avoid this
> problem.
>
> Micha

Hi Micha

>From what I understand strtr only replace characters, not sentences,
so I am not sure if that would work.

Cheers

Nicolaas