wrap

Type

operator

Summary

Wrap allows the user to ensure the value of a variable stays within a specified range.

Syntax

<number> wrap <divisor>

Description

The wrap function makes it easy to loop successively over a fixed number of items in a list. When cycling through the items of a list, the divisor parameter specifies which item will cause the cycle to loop back to the beginning of the list. This means that any number outside this range is mapped to a number within it.

For example, if we had 5 wrap 3, the number 5 would be mapped to the number 2 as this is where the iterator would be pointing on the 5th iteration ie. 1, 2, 3, 1, 2 . Therefore 5 wrap 3 is 2.

The mathematical formula implemented by the wrap operator is:

    x wraps y        =       ((x-1) mod abs(y)) +1 if (x >= 0)

= -((x-1) mod abs(y)) +1 if(x < 0)

If a math operation on finite inputs produces a non-finite output, an execution error is thrown. See math operations for more information.

Parameters

Name	Type	Description
number
divisor

Examples

repeat with x = 1 to 10
  put item x wrap 3 of "1,2,3" & comma after tOutput
end repeat
-- evaluates to 1,2,3,1,2,3,1,2,3,1

repeat with x=1 to 9
    put item x wrap 2 of "1,2" & comma after tOutput
end repeat
--evaluates to 1,2,1,2,1,2,1,2,1

Related

glossary: math operation

operator: slash

Compatibility and Support

Introduced

LiveCode 2.9

OS

mac

windows

linux

ios

android

Platforms

desktop

server

mobile