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BinaryZero

variable value to identifier

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BinaryZero    122
i need to change the value of a vaiable into an identifier for example if i="hello", the value "hello" can somehow be used as an identifier name it is possible please someone hell me how

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Chem0sh    122
It''s very simple. You can''t (at least not there''s no way I know of).

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BinaryZero    122
the ## operator concatenates two identifiers for example if i said i##j it would return me ij as one variable identifier. if there was a way to use the value of a variable name as and identifier i could set a counter and tell it i##*counter which would return me i1, i2, i3... etc

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dalleboy    324
You could use a string to object map.
std::map<std::string, int*> mapStringToInt;
mapStringToInt["hello"] = new int(47);
std::cout << *mapStringToInt["hello"];
EDIT: Darn HTML tags...

[edited by - dalleboy on June 9, 2002 6:39:21 PM]

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Michalson    1657
quote:
Original post by BinaryZero
the ## operator concatenates two identifiers for example if i said i##j it would return me ij as one variable identifier. if there was a way to use the value of a variable name as and identifier i could set a counter and tell it i##*counter which would return me i1, i2, i3... etc


For that purpose why not use an array? I believe Visual Basic can do something like this, however be warned, no matter what language you do it in it will be very slow. When a compiler creates machine code it converts variable names into memory addresses/offsets (the names you give them are meanless to the computer and are discarded). By accessing a variable "by name" you would have to look up the name in some form of table (as dalleboy described) to get the correct address. This would be extremely slow and consume lots of memory (assuming every varible in your program could be accessed in this way).

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Fruny    1658
quote:
Original post by dalleboy
EDIT: Darn HTML tags...



Use a [‍source] box, or stick &zwj;''s (zero-width joiner) in the appropriate places.

std::map::find() is more appropriate for a lookup than map::operator[]()

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felonius    122
>> return me i1, i2, i3... etc

yes, or even just an array i[1], i[2], i[3] instead of i1, i2, i3.

[edited by - felonius on June 9, 2002 6:52:13 PM]

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