CMSC 433, William Pugh, Univ. of
Maryland
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CMSC433, Spring 2001
Programming Language Technology
and Paradigms
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C++
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C++ without Classes
• Don’t need to say “struct”
• New libraries
• function overloading
– confusing link messages
• default parameters
• void *
– C++ requires explicit conversion from void *
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More C++ without Classes
• Dynamic initialization of globals
– no way to control order between files
• References
– Compiler treats as pointers
– Programmer doesn ’t
– Once initialized to reference an address, cannot
be made to reference a different address
– Used for pass-by-reference parameters
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References
int x,y;
int *p = &x;
int &q = y;
q++; // increments y
*p++; // increments p, returns value of x
(*p)++; // increments x
q = x; // assigns value of x to y
p=&y; // makes p point to y;
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new/delete
• use new A to allocate one A
• use new A[num] to allocate an array of num
A’s
• use delete to free one A
• use delete[] to free an array of A
• invokes constructors and destructors
– for all elements of an array
– delete[] must be given pointer to first element
