Search results
Results From The WOW.Com Content Network
The detailed semantics of "the" ternary operator as well as its syntax differs significantly from language to language. A top level distinction from one language to another is whether the expressions permit side effects (as in most procedural languages) and whether the language provides short-circuit evaluation semantics, whereby only the selected expression is evaluated (most standard ...
Unlike function and class names, variable names are case-sensitive. Both double-quoted ("") and heredoc strings allow the ability to embed a variable's value into the string. [13] As in C, variables may be cast to a specific type by prefixing the type in parentheses. PHP treats newlines as whitespace, in the manner of a free-form language.
In computer programming, lazy initialization is the tactic of delaying the creation of an object, the calculation of a value, or some other expensive process until the first time it is needed. It is a kind of lazy evaluation that refers specifically to the instantiation of objects or other resources.
if discount < 11% then print (you have to pay $30) elseif discount<21% then print (you have to pay $20) elseif discount<31% then print (you have to pay $10) end if; In the example above, if the discount is 10%, then the first if statement will be evaluated as true and "you have to pay $30" will be printed out.
Uninitialized variables are powerful bugs since they can be exploited to leak arbitrary memory or to achieve arbitrary memory overwrite or to gain code execution, depending on the case. When exploiting a software which utilizes address space layout randomization (ASLR), it is often required to know the base address of the software in memory.
Using non-owned memory: It is common to use pointers to access and modify memory. If such a pointer is a null pointer, dangling pointer (pointing to memory that has already been freed), or to a memory location outside of current stack or heap bounds, it is referring to memory that is not then possessed by the program. Using such pointers is a ...
A memory debugger is a debugger for finding software memory problems such as memory leaks and buffer overflows. These are due to bugs related to the allocation and deallocation of dynamic memory . Programs written in languages that have garbage collection , such as managed code , might also need memory debuggers, e.g. for memory leaks due to ...
In many languages (e.g., the C programming language) deleting an object from memory explicitly or by destroying the stack frame on return does not alter associated pointers. The pointer still points to the same location in memory even though that location may now be used for other purposes. A straightforward example is shown below: