Sven Barth: > Pascal is a language where declaration and use of > variables is separated. It makes it easy to see what > variables are declared and what type they are. Inline > variables mess this up as a variable can be declared > somewhere inside the code. I use C++ to earn my living. I > know why I'm not a fan of inline variables as I've been > biten by them often enough already.
I agree for my own reasons. As Wirth himself pointed out in the title of a book, programs comprise two conceptually separate parts: data structures and algorithms that work on them. The separation of variable declaration and their use follows this view, so that every Pascal routine has a data declaration/definition section and an executable begin..end block. This beautiful concept forms a cornerstone of all Wirth languages and is certainly worth keeping. I find code with intermixed variable declarations less readable because the declaraions no longer stand out but are buried within imperative statements. In order to navigate to a variable declaration from the point of its use other than the first one, the reader must scan the whole subprogram upwards, rather than the small declaration section. Intermixed variable declarations harm perception. When reading an algorithm, I am focused on what it does. Whenever I encounter a new variable declared in the middle of a function body, I have to perform a mental context switch and update the data model associated with the algorithm. Whenever the programmer grows annoyed of jumping to the declaration section and back to code, he knows it is time to cut his spaghetti into more manageable parts. Inline variables are simply ugly, disrupting the aesthetical rhythm of code: a := a + Func1( b ); int b := Func2( a ); a := a - Func3( b ); Also worth reference are Bart's thoughts on the subject, in two parts: http://al.howardknight.net/msgid.cgi?ID=155215407800 http://al.howardknight.net/msgid.cgi?ID=155215418300 Please, do not turn Pascal into another C# or Java. -- Please, do not forward replies to my e-mail. _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
