Re: Pointers to "why C behaves like that ?"

Robert A Duff wrote:
> The reason is not historical. There are some very old languages that
> do *not* require declarations. For example, Fortran, which predates
> C, has this weird rule that the compiler should guess the type of each
> variable by looking at the first letter of its name.


This serves the same function: see a variable, know its attributes. Of
course variable types in FORTRAN were quite limited.


PL/I doesn't require declarations, since it's a two-pass compiler that
can pretty well figure out the type of a variable based on its usage
by the end of pass 1, before any code is generated.


C, being designed for a much more limited computer than PL/I, was
designed to be one-pass, which would require declarations, since it
has a larger range of data types than FORTRAN. Unfortunately once a
language gets implemented it's pretty hard to change things like this
when better hardware becomes available.


I believe (IMHO) that nowadays the consensus is that having to declare
everything is a "good thing" since it acts as a check against spelling
errors.

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