INTRODUCTION

If you come from a C++ background, it's likely you have a very "compile-time"
view of the world. Because a C++ compiler does all code generation when the code 
is compiled, C++ programs are static systems that are fully known at compile time. 

The Common Language Runtime provides a new way of doing things. The compile-time
world still exists, but it is also possible to build dynamic systems where new code
is added by loading assemblies or even by writing custom code on the fly.

ABOUT "RUN TIME CODE GENERATOR"

This products provides very efficient way of handling user requests manipulating with
elements of collections. Request is just string with valid CSharp expression. Code generator
generate new class which Apply method returns result of calculation of this expression. 
So it can be used as very fast query system which selects objects from the collection
according to user specified criteria (very small database engine).It can be also used 
if you want to perform some user specified calculation for all members of the collection.
Collection can consists of just one element, in this case code generator can be used as
very fast calculator. 

Certainly dynamic code generation makes sense only when expression once specified 
will be executed multiple times or it will be applied to collection with large number 
of members.


HOW TO USE

This product currently generates two kind of objects: collection filters and mappers.
Filter is used to select members of collection matching user supplied criteria.
Mapper is used to perform some calculation for all members of the collection and 
create new collection with results of such calculation.
 
Classes MapperGenerator and FilterGenerator are used to generate mappers and filters correspondently. 
Constructor of this class requires type of collection members (it is assumed that
al elements of the collection are of the same type or derived from this type) and
size of the cache of generated classes. Cache is used to reduce number of generated methods.
Generator will first look for expression in the cache and if it was already generated, the result
is reused. 

Generate method of MapperGenerator and FilterGenerator class requires string argument with
expression and returns mapper of filter. This mapper or filter can be then applied to the particular
collection using Apply method. Result is another collection. In case of filter, it contains
elements from the original collection for which specified condition is true. For mappers it contains
results of calculation of specified expression for each element of original collection. 
Result collection can be converted to array using ToArray method or be iterated using foreach construction.


WHAT CAN BE IN EXPRESSION

Expression can contains any valid CSharp operation with constants and fields of the object (collection element).
Type of this object was specified in generator constructor. It is possible to invoke static and instance methods. 
Currently arrays, unsigned type and unsafe pointers are not supported. Also overloading resolution rules are slightly 
different from CSharp.

LICENSE

This is public domain product. It is distributed without any warranty, but I will perform e-mail support of it.
You can do with it everything you want except copyrighting it. 
If you need to use dynamic code generator for some other purposes (except filtering and mapping collection), 
I will be glad to help you to develop such system.