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From: Cheyenne Wills <[e-mail]>
To: [e-mail]
Subject: Re: How to "declare" a string?
Date: Mon, 23 Oct 2000 10:59:15 +0100 (MDT)
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Icon handles datatyping differently then languages such as C, or Java.
Icon will try to convert the datatype to the apporiate type needed by the
current operation.

For example:

some_number := 1234
a_string = "this is a string"

new_number := some_number + 5  # -> 1239
new_string := a_string || "."  # -> "this is a string."

another_string := "4" || "2"   # -> "42"
some_fun := another_string + 3 # -> 45
more_fun := a_string || some_number # -> "this is a string1234"

Also one does not need to "declare" variables before using them.  They all
have a default value of &null.  What this means is that as long as the
first time the variable is used in a expression it is either "recieving a
value" or it is tested for null.

For example:

procedure main()
   repeat {
      if /count then count := 5   # First checks to see of varable is null
      if count > 10 then break
      count := count + 2
   }
end

This can be rewritten as:

procedure main()
    repeat {
        /count := 5
        (10 >= count) +:= 2
    }
end

The above relies on two features of Icon, one the behavior of failure
within expressions and the fact that an expression can return (produce) a
"variable"

Cheyenne