NewBie's Corner Session 7 True and False
Welcome to NewBie's Corner, a weekly or biweekly post covering basic Caché Material.
Click on the Caché Cube in your system tray and select Terminal to try out these commands.
In COS, a 0 is false and any other number (positive or negative) is true.
Set X=1
If X Write "True" ; 1 is true and 0 is false
True
Set X=0
If X Write "True" ; 0 is false
<>
Set X=10
If X Write "True" ; Any number other than 0 is true
True
Set X=-10
If X Write "True" ; Any number other than 0 is true, even negative ones
True
Set X="1"
If X Write "True" ; 1 is true even in alphanumeric text
True
Set X="0"
If X Write "True" ; 0 is false in alphanumeric text
<>
Set X="01"
If X Write "True" ; Some of these are tricky
True
Set X="1ABC"
If X Write "True" ; The 1 is used and the rest of the text is ignored
True
Set X="0ABC"
If X Write "True" ; The first numeric is used and the rest of the text is ignored
<>
Set X="ABC1" ; If the numeric is not the first character,
If X Write "True" ; the whole string is ignored
<>
True and False with alphanumeric text
- When alphanumeric text (quoted string) contains only a numeric it is evaluated as pure numeric
- When alphanumeric text (quoted string) has as its first characters a numeric, the numeric is used as a pure numeric, and the rest of the alphanumeric text is ignored
- When alphanumeric text (quoted string) has as it first characters an alpha character, the whole string is evaluated as 0 or false
I suggest you spend some time on the Terminal trying some of these combinations. They are not always as obvious as you think.
--Mike Kadow
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