SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
length, the shorter string is considered to be extended with blanks for comparison purposes. Comparisons
are not limited to equality or inequality. However, the result of "less than" or "greater than"
comparisons depends on the collating sequence of the internal character sequence used. This is
based on the implementation and the SIMSCRIPT II.5 User Guide should be consulted. On all implementations,
however, the null string compares less than all other strings.
2.21.1 Concatenation: CONCAT.F(text1, text2...textn)
The concat.f function returns a text variable by concatenating the text variables or text expressions
given as arguments. To illustrate the effect, let the text variables STRING1 and
STRING2 be assigned the characters "PIANO" and "FORTE", respectively. The effect of the statement:
let LONGNAME = concat.f(STRING1, STRING2)
is to assign the characters "PIANOFORTE" to LONGNAME. Similarly,
let LUNCH = concat.f("HAM", "AND", "EGGS")
assigns "HAMANDEGGS" to LUNCH. The concatenation is in the order of the given arguments. If any
argument has a null value, the remaining strings are concatenated normally.
2.21.2 Substring: SUBSTR.F(text, index, length)
The substr.f function provides access to a substring within a text variable. The substring is
specified by two integer values, a start position within the source string, and the substring length.
The first character of the string is referenced by an index of 1. If A and B are text variables, then the
statement:
let B = substr.f(A,I,J)
copies J characters, starting from the I th character position in A to the character string B. A remains
unchanged. For example, if A = "SIMSCRIPT II.5", then:
let B = substr.f(A,4,6)
assigns the characters "SCRIPT" to B.
Unlike most functions, substr.f may be used on the left-hand side of an assignment statement
to replace a substring within a text variable. If string A has the value "FOOTBALL", then the
effect of the statement:
let substr.f(A,1,4) = "GOLF"
is to replace the first four characters in A, giving it the value "GOLFBALL". For either use, the start
position specified must be 1 or greater. The substr.f function may not be used to extract or replace
characters beyond the length of the string, A. If the substring is so specified, only the remain-
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