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		.FUNCTION...END FUNCTION Statement Details.   QuickSCREEN      Details      Example      Contents      Index ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ FUNCTION...END FUNCTION Details Syntax   FUNCTION name [(parameterlist)][STATIC]       [statements]     name = expression       [statements]   END FUNCTION     Part            Description   name            The name of the function. FUNCTION names follow the                   same rules as BASIC variable names and can include a                   type-declaration character (%, &, !, #, or $). Note                   that the type of the name determines the type of                   value the function returns. For example, to create a                   function that returns a string, you would include a                   dollar sign in the name or give it a name defined as                   a string name by a DEFSTR statement.     parameterlist   The list of variables, separated by commas, passed                   to the FUNCTION. The parameters are passed by                   reference, so any change to a parameter's value                   inside the function changes its value in the calling                   program.     STATIC          Indicates that the function's local variables are to                   be saved between calls. Without STATIC, the local                   variables are allocated each time the function is                   invoked, and the variables' values are lost when the                   function returns to the calling program. The STATIC                   attribute does not affect variables that are used in                   a FUNCTION but declared outside the FUNCTION in DIM                   or COMMON statements using the SHARED attribute.     expression      The return value of the function. A FUNCTION returns                   a value by assigning a value to the function name.                   If no value is assigned to the FUNCTION name, the                   FUNCTION returns a default value:  a numeric                   function returns a value of zero, and a string                   function returns the null string ("").   A parameterlist has the following syntax:     variable[( )][AS type][,variable[()][AS type]]   A variable is any valid BASIC variable. The optional type can be either INTEGER, LONG, SINGLE, DOUBLE, STRING, or a user-defined type.   Earlier versions of BASIC required the number of dimensions in parentheses after an array name. The number of dimensions is no longer required. Only the parentheses are required to indicate the parameter is an array. For example, the following statement indicates that both Keywords$ and KeywordTypes are arrays:   FUNCTION ParseLine(Keywords$(),KeywordTypes())   A FUNCTION procedure is like a SUB procedure:  it can accept parameters, perform a series of statements, and change the values of its parameters. Unlike a SUB, a FUNCTION is used in an expression in the same manner as a BASIC intrinsic function.   Like SUB procedures, FUNCTION procedures use local variables. Any variable not in the parameter list is local to the FUNCTION unless it is declared as a shared variable in a SHARED statement, or unless the variable appears in a DIM or COMMON statement with the SHARED attribute.   To return a value from a function, assign the value to the function name. For example, in a function named BinarySearch, you might assign the value of the constant FALSE to the name to indicate the value was not found:     FUNCTION BinarySearch(...)   CONST FALSE=0   .   .   .     ' Value not found. Return a value of FALSE.        IF Lower>Upper THEN         BinarySearch=FALSE         EXIT FUNCTION      END IF   .   .   .   END FUNCTION   Using the STATIC keyword slightly increases execution speed. STATIC is not usually used with recursive FUNCTION procedures. See the examples below.   The EXIT FUNCTION statement provides an alternative exit from a FUNCTION. See the EXIT statement.   Because BASIC may rearrange arithmetic expressions to attain greater efficiency, avoid using FUNCTION procedures that change program variables in arithmetic expressions. Also avoid using FUNCTION procedures that perform I/O in I/O statements.   QuickBASIC FUNCTION procedures are recursive--they can call themselves to perform a given task. See the second example below.