SIMSCRIPT II.5 Programming Language

Programming Language Concepts
define variable list as alpha variables
An alpha variable may contain any character from the character set, including the blank character.
A character value is assigned to an alpha variable by delimiting the character literal with quotes
("). If the literal comprises more than one character, the first character is assigned. (When an
alpha variable contains more than one character, the number of characters equivalent to the alpha
variable size will be extracted.) For example:
let ALPHAVAR = "A"
The quotation mark is assigned by writing four successive quotation marks (""""). Alpha variables
may be assigned and compared. They may also be used in arithmetic operations, but care must be
taken that such use is meaningful. It must also be noted that the effect of such use may differ with
various implementations, as various internal character representations have different numeric values.
An example of the use of an alpha variable might be the use of alphabetic item codes in the
inventory program mentioned earlier:
define ITEM.CODE as an alpha variable
define STOCK as a 1-dimensional integer array
.
.
read ITEM.CODE and QUANTITY
if ITEM.CODE "X"
subtract QUANTITY from STOCK(ITEM.CODE)
always
.
.
However, a similar effect may be achived without resorting to such implementation-dependent code.
2.22.1 TEXT to ALPHA Conversion: TTOA.F(text)
The system function ttoa.f returns the first character(s) of the given text variable as an alpha
variable. Although typically only one character is returned, more may be given depending on the implementation
and computer option selected. If the null string is given, a blank character(s) is returned.
2.22.2 ALPHA to TEXT Conversion: ATOT.F(alpha)
A complementary function, atot.f, generates a text representation of the given alpha variable.
In general, this is a single character string, but alpha representation may vary on some systems.
Consult the user's manual.
2.23 Recursive Routines
All SIMSCRIPT II.5 routines are recursive, meaning that they can call upon themselves. The concept
of recursion is commonly exemplified using a procedure evaluating the factorial of a number.
The factorial of a number is defined by:
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