Programming Fundamentals

func_get_args() returns an array containing all arguments passed to the current function. This is useful for variable-length argument lists. Related functions: func_num_args() returns count, func_get_arg(n) returns single argument at position n.

func_num_args() returns the total number of arguments passed to a user-defined function. Unlike func_get_arg() (which gets a specific argument by index) or func_get_args() (which returns the entire array of arguments), this function only returns the count.

The list() construct in PHP assigns array elements to variables in a single operation, treating the array values as if they were being assigned to individual variables. It's commonly used with arrays that have numeric indices. For example: list($a, $b) = array(1, 2) assigns 1 to $a and 2 to $b.

array_walk() applies a user-defined callback function to each element of an array. This is useful for performing operations on every array element, such as formatting, validation, or transformation. The callback function receives the element's value and optionally its key and index.

Both require() and require_once() cause fatal errors and terminate the script if the included file cannot be found or cannot be opened. This is different from include() and include_once(), which only generate warnings and allow the script to continue. The '_once' variants ensure the file is included only once even if called multiple times.

Call by reference mechanism uses another name of arguments.

Encapsulation feature of OOPs hides data from the user.

A function or group of functions that differ in the types of parameters they use is called function template.

This data structure of the compiler, stores constants and strings used in a program.

Semaphore is a shared integer variable with non-negative values, which can only be subjected to initialization and invisible operations.

Code files can obtain a symbol table - a table indicating the names of all functions and global variables, and the virtual addresses that correspond to.

This function is used to add/append the content of the source string into the content of the target string.

This string function is used to copy first n characters of one string to another string.

This function pushes the character read previously using getc() back into input stream pointed to by the file pointer.

This operator is used in the context of closes and in providing a global scope for the variable.