NewBie's Corner Session 7 True and False

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

PaulMikeKadow@gmail.com

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