E is a expression
ES consists of at least zero expressions splited by at least one Space or Line Feed
V and V_ are expressions that consist of any char expected # or $ or " or ' or ( or ) or Space or Line Feed
$V is a expression that is constant
#V is a expression that is V (NOTICE: Not V's value)
V(ES) is a expression that receives one value as V's value and returns (ES)'s value:
V belongs the global space in default
V and V_ in V(ES) belong the local space
(ES) is a expression that is calculated in the following way:
()'s value is $nil
(E)'s value is E's value
(ES E)'s value is the value returned after passing E's value to (ES)'s value ((ES) will be calculated ahead of E)
$(ES) is a expression that is a tuple:
$(ES)'s value consists the value of each expression in ES (Exressions in ES will calculated from left to right one by one)
#(ES) is a expression that calculated in the following way:
#(ES)'s value is (ES) (NOTICE: Not (ES)'s value)