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Typed CL
--------

Typed CL is an extension to Common Lisp which allows for the typed
decleration of functions and variables.  Under the hood, it takes the
type information and writes the declerations for you, making your code
not only easier to read and safer (due to compiler type checks), but
it also gives the compiler more information for optimization and
(should) make your code run faster.

Some might say that dynamic typing is one of the best features of
Common Lisp.  The point of this project is twofold: during initial
writing and during editing/optimization.  You can hack with no types
and add them in later, or you can write them in during inital coding.
I find the syntax simpler and clearer than adding your own type
declerations by themselves.

Usage
-----

Typed CL comes with an asdf package that can be loaded or required as
needed.  I will look into adding it to quicklisp in the future.

Examples
--------

A simple example:

(def number square ((number x))
     (* x x))

def is exactly like defun except for including the return type and
function parameter types.  

A helper type 'list-of' is included to show how you can create
programmably verified types for your parameters:

(def integer sum (((list-of integer) l))
     (vars ((integer sum 0))
	   (dolist (n l)
     	     (setf sum (+ sum n)))
	   sum))

The above example also shows how to use the vars/vars* macros.  ldef
is the analog of labels with type information and follows the same
convention/syntax as def.

Essentially, adding type information just means to wrap your
parameters/variables with an extra set of parens, and put the type of
before the name and the default value after.

The real benefit is with safety > 0.  At least with SBCL it will give
plenty of warnings when the types do not match what is defined in the
signatures and declerations.

Care has been taken to provide decent warning/error messages on
invalid syntax but it's not perfect.  Sometimes the messages are a bit
hard to decipher.

--
Burton Samograd <[email protected]>