Only the true path in the If...Then...Else statement
It probably refers to "scope" (see http://en.wikipedia.org/wiki/Scope_(programming)). In programming languages with lexical scope, variables declared in an outer scope can be used in an inner scope, but variables declared in an inner scope cannot be used in outer scopes. It is considered best practice to declare variables (and constants, which are just variables that don't change) at the innermost scope possible for several reasons: # It makes it most clear what the scope of use is of the variable. # It makes it impossible to mistakenly use it in some other location. # It makes it easier to keep track of what variables exist at any given point in the code. For example, in standard C, nested functions are not allowed. This means that in any function, only two types of variables exist - global variables, and variables declared within that function. This has the advantage of making it easy to understand what any variable refers to.
A local variable only exists within the scope in which it is declared. As soon as the scope ends, the variable ceases to exist. { // beginning of a scope, i does not yet exist int i = 42; // local variable declared, i now exists } // end of scope, i no longer exists
Local function variables defined static remain in memory at all times. Such variables are only in scope (accessible) when the function itself is in scope.
Automatic variables are variables that are declared within the scope of a block, usually a function. They exist only within that scope, i.e. that block, and they cease to exist after the block is exited. These variables are usually allocated from the stack frame.
The Scope of a variable defines the areas of a program where this variable would be visible and can be used. For ex: a. Method variables - are visible only inside the method where they are declared and hence their scope is only the method b. Class variables - are visible inside the class and can be used by any method inside the class and hence their scope is the whole class.
The block they are declared in.
It probably refers to "scope" (see http://en.wikipedia.org/wiki/Scope_(programming)). In programming languages with lexical scope, variables declared in an outer scope can be used in an inner scope, but variables declared in an inner scope cannot be used in outer scopes. It is considered best practice to declare variables (and constants, which are just variables that don't change) at the innermost scope possible for several reasons: # It makes it most clear what the scope of use is of the variable. # It makes it impossible to mistakenly use it in some other location. # It makes it easier to keep track of what variables exist at any given point in the code. For example, in standard C, nested functions are not allowed. This means that in any function, only two types of variables exist - global variables, and variables declared within that function. This has the advantage of making it easy to understand what any variable refers to.
Scope of static variable is with in the file if it is static global. Scope of static variable is with in the function if variable is declared local to a function. But the life time is throughout the program
A local variable only exists within the scope in which it is declared. As soon as the scope ends, the variable ceases to exist. { // beginning of a scope, i does not yet exist int i = 42; // local variable declared, i now exists } // end of scope, i no longer exists
Local function variables defined static remain in memory at all times. Such variables are only in scope (accessible) when the function itself is in scope.
Automatic variables are variables that are declared within the scope of a block, usually a function. They exist only within that scope, i.e. that block, and they cease to exist after the block is exited. These variables are usually allocated from the stack frame.
The Scope of a variable defines the areas of a program where this variable would be visible and can be used. For ex: a. Method variables - are visible only inside the method where they are declared and hence their scope is only the method b. Class variables - are visible inside the class and can be used by any method inside the class and hence their scope is the whole class.
A function typically consists of a name, parameters (inputs), a return type (output), and a block of code that performs a specific task or calculation. Additionally, a function can have local variables declared within its scope and can sometimes have a return statement to send a value back to the caller.
In computer science, "local" typically refers to data or variables that exist and are accessible within a specific scope or context, such as within a function or a block of code. Local variables are usually declared and used within a limited area of a program, and their scope is restricted to that particular area.
Scope determines the lifetime of non-static names, as well as the visibility of both static and non-static names, when constructors and destructors are called and when member variables are initialised. Names can be applied to any type of variable, including instances of a class (objects).There are five distinct types of scope in C++:Local scope: names declared within a statement block are accessible only to that block and the blocks contained by it, from the point of declaration onwards. This includes the formal names of arguments to a function.Function scope: labels are the only names that have function scope.File scope or namespace scope: any name declared outwith all blocks and classes has file scope. Non-static names are usually referred to as global names.Class scope: Names of private class members have class scope, which includes friends of the class. Names of protected members extend their scope to derivatives of the class. Names of public members extend their scope outwith the class.Prototype scope: Names declared in a function prototype are only visible until the end of the prototype.
A variable declared static outside of a function has a scope the of the source file only. It is not a global variable. A variable declared outside of a function and without the static qualifier would be a global variable.
1. Local variables cannot be used by other forms. 2. Cannot be used globally. 3. They can slowdown the compiling process.