Thread: Though implementation problem

Originally Posted by Elysia

No, it's not the interface per se that's the problem, but the internal mechanisms.
And it should be Replace(What, With, Start, End).

How you compare if a subsequence is equal to "what"?
And why do you need start/end?

Originally Posted by Elysia

Subsequence equal to what?

If I understand you right, then you probably want to replace "This" with "That" in following sentence:
"This is a tree."
Right?

So if in your example Replace(what, with, start, end):
what - "This"
with - "That"
Then how will your generic solution compare if the sequence to be replaced is actually equal to "This", which is not a single word, but, generically speaking, a sequence of elements.

How will you compare such sequence within the destination sequence, which needs the replacement!?!

I am speaking generically! Reusable ofcourse!!

Other wise forget the bling-bling-blah!
And, just think, how to replace words within a string, in simple yet efficient manner!

If you only want to perform and search and replace within a specific region.However, there will also be overloads that doesn't take start or begin (will perform search & replace on whole string).

Extra features never hurt! Make them some default arguments! So I need not concern myself with them!

Originally Posted by Elysia

Err hello? How it a problem to replace a string? We've done that a hundred times and that implementation is already done. A long time ago.

So you are not writing a single generic function that could replace any sequence with another sequence? Ok never mind.

Yes, also unfortunately, the C++ standard forbids initializing default arguments with a non-static value (I think I'm getting this right), and also references must be initialized with a const value.

Code:

void Replace(const CTmplStringBase& strReplaceWhat,
    const CTmplStringBase& strReplaceWith);
void Replace(const CTmplStringBase& strReplaceWhat,
    const CTmplStringBase& strReplaceWith, const const_iterator& vStart);
void Replace(const CTmplStringBase& strReplaceWhat, const CTmplStringBase& 
    strReplaceWith, const const_iterator& vStart, const const_iterator& vEnd);

You can choose whichever version suits you best.

Thanks for you efforts. I just want to do this:

Code:

CStringEx("This is ${NAME}!").Replace("${NAME}", getName());

Originally Posted by Elysia

I don't know what you're on about.

Well replacing (as in the real meaning), is easy, but only if the "with" is equal in length to "what".
Otherwise see this string:
CStringEx str("Name: {1}\nOver draft {2}\nInterest {3}\n");
and this Replace usage:

Code:

str.Replace("{1}", "Elysia Petralovech");
str.Replace("{2}", "7500.50");
str.Replace("{3}", "250.50");

Do you see, that, every replacement is increasing the string size?
And do you also see that this is basically a sub-sequence insertion over the deletion?

Does that sound a generic solution bell?

May be a generic == operator also, which can compare sub-sequences and return start/end iterator pair?

// I think they have brain washed me more than enough, boy, I am also thinking generically now!!!

Originally Posted by Elysia

My implementation does move around to make room.

Code:

Strings::CStringEx str = "{1} is a tree";
cout << str << endl; // {1} is a tree
str.Replace("{1}", "That");
cout << str << endl; // That is a tree

Of course your implementation does/would have it! I was just asking, that, are you doing it for strings only, or for any kind of sequences?

Anyway, never mind now! I am just waiting for your first Alpha release

Originally Posted by Elysia

It would work with any given type, but it only works on a element basis.
You can't expect a sequence of values to be treated as one value or element.

I got it (I was thinking something similar).

Boost isn't letting me define a proper return type for my operators -/+...
After that... well... Well, after that's over and done with, I guess major testing is due.

I understand the '+', but what is '-' for?

Would you enable this in your string class?

Code:

CStringEx str;
int age = 23;
float cm = 167.1f;
str << "She is " << age << " years old, " << cm << " centimeter high!" << endl;

Originally Posted by Elysia

Iterators.
Iter1 + Iter2
OR
Iter1 - Iter2
I really need to implement a range iterator here or some such. A lot of thinking left there.

Ok got it

No, but this would work:

Code:

CStringEx str;
int age = 23;
float cm = 167.1f;
str = "She is "+ age + " years old, " + cm + " centimeter high!";
cout << str << endl;

Or rather, float and doubles don't work. At least not yet, but maybe in the future. But integers works.

That's even better! I already feel like being in heaven!
Release your implementation pretty soon!!