[OT] -10^2
Klaus Major
klaus at major-k.de
Thu May 22 12:15:00 EDT 2003
Hi folks,
>> Hope I don't get flamed for this, but I don't agree.
>> :-) Someone feel free to dispute me if I'm wrong, but
>> I think Rev is correct. Isn't -10^2 the same as -10*-10
>
> Totally agree with you...
> I read -10^2 as (-10)^2 not -(10^2)
>
> As the interpretation seems to be in the eye of the beholder, then to
> save
> creating any doubt I'd always recommend parenthesis.
>
> Gary Rathbone BSc MBCS
sorry, this is a lenghty but necessary post ;-)
This is from the MC help file and help understand what RR is doing here:
(...and is a good info anyway ;-)
> Operators:
>
> Order 1:
> () # groups an expression
>
> Order 2:
> - # unary minus (e.g., -4)
!!!
Yes, i also was a bit surprised by that...
This operator comes BEFORE...
> not # make the opposite of a boolean
> bitNot # bitwise negation
> there is # check existence of an object
>
> Order 3:
> ^ # raise a number to a power
...this one, which should explain RRs behaviour...
> Order 4:
> * # multiply two numbers
> / # divide one number by another
> div # integer divide (no fractional part)
> mod # remainder after a div
>
> Order 5:
> + # add two numbers
> - # subtract two numbers
>
> Order 6:
> & # concatenates two strings
> && # concats, but inserts a space
> , # concats, but inserts a comma
>
> Order 7: compares numbers or strings (boolean)
> < # less than
> <= # less than or equal to
> > # greater than
> >= # greater than or equal to
> contains # first string contains second
> is among # first string is a whole chunk in second
> is not among # first string is not a whole chunk in second
> is in # first string is a substring of second
> is not in # 1st string is not a substring of 2nd
> is within # point is in a rectangle
> is not within # point is not in a rectangle
> is a(n) # type check
> is not a(n) # type check
>
> Order 8: compares numbers or strings (boolean)
> = # equal
> <> # not equal
> is # equal
> is not # not equal
>
> Order 9:
> bitAnd # bitwise and
>
> Order 10:
> bitXor # bitwise exclusive or
>
> Order 11:
> bitOr # bitwise or
>
> Order 12:
> and # compare boolean expressions
>
> Order 13:
> or # compare boolean expressions
>
> The boolean operators return either true or false and can be used as
> the condition of an if construct. The bitwise operators can only be
> used on numbers, and operate directly on the binary representation of
> the numbers.
>
> The validation operator "there" is used to verify that an object
> exists before trying to access it. You can use it with any object
> type (background, button, card, field, group, image, scrollbar, stack)
> or the word "file", "directory", or "process". For example, to
> prevent errors when a user clicks on a term that does not have a card
> describing it, the following statements are used in a mouseUp handler
> in this stack:
>
> if there is a card the clickText
> then go to card the clickText
>
> The sense of the "there" operator can be reversed with the word "no"
> as in:
>
> there is no file "myfile.txt"
>
> The is operator can be used to compare strings or numbers, as strings
> or numbers, but also to determine if the source is a complete chunk
> (word, item, or line) within the destination. This use is similar to
> the contains operator, and the itemOffset, lineOffset, and wordOffset
> functions when the wholeMatches property is set to true:
> put "3" is among the items of "22,33,44" #returns false
> put "3" is among the words of "2 3 4" #returns true
>
> The is operator can also be used as a validation operator:
>
> if field "size" is a number
> then add 10 to field "size"
>
> The types that can be verified are date, number, integer, point, rect,
> and boolean.
Hope that helps...
Regards
Klaus Major
klaus at major-k.de
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