sonsi - Stupid and Obvious Non-recursive Scheme Interpreter

	Commit message (Expand)	Author	Age
*	new targets in TODO-list	Teddy	2013-08-04
*	added more error report	Teddy	2013-08-04
*	added exception facilities	Teddy	2013-08-04
*	replaced many `dynamic_cast` to `static_cast`	Teddy	2013-08-04
*	modified the API of Env: add_binding	Teddy	2013-08-04
*	added more docs	Teddy	2013-08-04
*	C++ version now works!	Teddy	2013-08-03
*	AST parser can now work!	Teddy	2013-08-03
*	transfering the implementation language to C++	Teddy	2013-08-02
*	put sketch files into `prototype` and important structural improve on sketch.py	Teddy	2013-08-02
*	use a simple and elegant way to represent the AST	Teddy	2013-07-31
*	the project should be obvious, which is my greatest hope	Teddy	2013-07-31
*	added comments and adjusted the construction of AST	Teddy	2013-07-31
*	changed name	Teddy	2013-07-31
*	add procedure definition syntatic-sugar	Teddy	2013-07-31
*	more friendly input	Teddy	2013-07-31
*	add support for multiple expressions in lambda	Teddy	2013-07-31
*	revised the poor fix of cont. exiting to a better one	Teddy	2013-07-31
*	use simpler mask routine	Teddy	2013-07-31
*	The prototype is nearly finished! Tests are welcome.	Teddy	2013-07-31
*	added lambda-statement	Teddy	2013-07-30
*	...	Teddy	2013-07-30
*	added if-statement	Teddy	2013-07-30
*	simple evaluation	Teddy	2013-07-30
*	added README	Teddy	2013-07-29
*	init	Teddy	2013-07-29