X-Git-Url: https://ruin.nu/git/?p=proglang.git;a=blobdiff_plain;f=documentation;h=bbb604f08eb7bb7225e8219460a812238e158726;hp=cb693df417c88f4430589c5ac0de2ce533360c91;hb=d553df8dfdffca78342d6fae142ceded9cd64415;hpb=67721d82f79e56db9c728aed76a3ad9dcca005c2

diff --git a/documentation b/documentation
index cb693df..bbb604f 100644
--- a/documentation
+++ b/documentation
@@ -1,77 +1,143 @@
 ####### DOCUMENTATIATOIAITAT ION ########
 
 
+Files:
+Typechecker.hs: Simple modification of the bnfc-generated Testsyntax which calls the type-checking functions.
 
+Typecheck.hs: Contains the type-checking functions typeCheckExp, typeCheckVar and typeCheckStm and some utility functions, responsible for the entire type-checking process.
 
-a simple c-like language with support for if/else-statements, while-loops and the standard arithmetic (+, -, /, *) and comparison expressions (<, >, <=, >=, ==, !=). also, increase/decrease expressions (++, --) are supported.
+Abssyntax.hs, Parsyntax.y, Lexsyntax.x,ErrM.hs,Printsyntax.hs,Skelsyntax.hs: The files generated by bnfc, only modification is the removal of the Bool type in Abssyntx.hs so haskell's internal type can be used.
 
-data types:
-integers and booleans.
 
-comments:
-// and /* */ comments are allowed.
+typing rules
+++++++++++++
 
 
+(t is used for types, T is the context, and + is used for in)
 
 
+[Eq, NEq]
 
+T+ e1 Eq e2:bool  <=  T+ e1:t  &  T+ e2:t
 
+If e1 and e2 are of the same type, then Eq or NEq return bool
 
 
+[Plus, Minus, Times, Div]
 
+T+ e1 Plus e2:int  <=  T+ e1:int  &  T+ e2:int
 
+The operators Plus/Minus/Times/Div return int if both operands are ints
 
 
+[Lt, ELt, Gt, EGt]
 
-examples:
+T+ e1 Lt e2:bool  <=  T+ e1:int  &  T+ e2:int
 
-fib
----
-int n1 = 0;
-int n2 = 1;
-int n = readInt;
+The operators Lt/ELt/Gt/EGt return bool if both operands are ints
 
-while(n-- > 0){
-  int temp = n1+n2;
-  n1 = n2;
-  n2 = temp;
-}
-print n2;
 
+[Assignment]
 
-tests while, decr and assignment.
+T+ i := e:t  <=  i:t in T  &  T+ e:t
 
+The assignemnt of e to i returns type t if both i and e have type t.
 
 
-if
---
-if (readBool) {
-  if (readInt < 0)
-    print true;
-  else
-    print false;
-}
+[ENeg]
 
+T+ ENeg e:int  <=  T+ e:int
 
-tests if and if/else.
+ENeg e returns int if e is of type int
 
+[ENot]
 
+T+ ENot e:bool  <=  e:bool
 
-sum
----
-int n;
-int sum = 0;
-while ((n = readInt) != -1) sum = sum + n;
-print sum;
+ENot e returns bool if e is of type bool
 
+[EVar]
 
+T+ i:t <= i:t in T
 
+i has type t if i is defined in the context with type t.
 
-var
----
-int a = 3;
-int b = a - 5;
-int c = a + b*7;
-bool d = a == b;
+[EInt]
 
-tests simple variable operations.
\ No newline at end of file
+T+ n:int
+
+n has type int
+
+[EBool]
+
+T+ b:bool
+
+b has type bool
+
+[EReadI]
+
+T+ n:int
+
+EReadI returns an int
+
+[EReadB]
+
+T+ b:bool
+
+EReadB returns a bool
+
+[EPost]
+
+T+ EPost i:int <= i:int in T
+
+EPost i is of type int if i is defined in T with type int.
+
+[SExp]
+
+T+ e   <=  T+ e:t
+
+[SBlock]
+
+T+ s;SBlock ss <= T+ s => T' , T'+ ss => T''
+
+the first statment s, in the block, is typechecked in the context T and returns the context T', the rest of the block is then recursively typeckecked in the context T' 
+
+
+[SIf]
+
+T+ if e then s1 else s2  <=  T+ e:bool  &  T+ s1  &  T+ s2
+
+if e is of type bool and s1 and and s2 typechecks in the context T, then the same context is returned
+
+
+[SWhile]
+
+T+ while e do s  <=  T+ e:bool  &  T+ s
+
+If e is of type bool and s typechecks in context T then the same context is returned
+
+
+
+[SDecl]
+
+T+ t i = e => T,i:t  <=  i not in T  &  e:t 
+
+if i and e are of the same type and i is not declared in the current scope then i is added with type t to the context.
+
+[SDeclD]
+
+T+ t i => T,i:t  <=  i not in T
+
+if i is not declared in the current scope, then i is added to the context with type t
+
+[SNoop]
+
+T+ s
+
+SNoops does nothing so the same context is returned
+
+[SPrint]
+
+T+ e <= T+ e:t
+
+if e has type t then SPrint returns the same context