Changeset 187 for trunk/thune/doc

Timestamp:

06/20/06 05:09:27 (3 years ago)

Author:

krobillard

Message:

Thune - Major improvement to the handling of local function values.
Locals can now be passed to inner functions and caught when returned.
Functions are no longer tied to the thread which created them.

The localArgBlk has been eliminated and locals are now stored on the stack.
To accomodate this, the data stack is now separate from the control stack
and grows upwards. This also means that functions can no longer access the
stack below the function call. A limit of one returned value is in place.

To regain full stack usage, locals could be stored on the control stack.
The only downside would be an extra copy of arguments from the data to
the control stack.

ur_wordCell() is now a function rather than a macro.

uc_do() has been merged into ur_eval() and 'do is now implemented as an opcode.

. & .s now use uc_console_out() rather than dprint.

Files:

• trunk/thune/doc/UserManual (modified) (2 diffs)

trunk/thune/doc/UserManual

@@ -110 +110 @@
 Functions can be defined in two ways: as procedures or as functions.
 
-Procedures are a block of code.
-
-Functions are procedures with local arguments and variables.  These local
-values are declared in a signature block.  When a function is called the
-arguments are copied from the stack and then dropped.
+Procedures are simply blocks of code which can be evaluated.  Any number of
+values may be removed from or pushed onto the stack by a procedure.
 
 ::
@@ -120 +117 @@
     ; Here is a procedure
     ["Hello World" print] proc :hello
+
+Functions are blocks of code bound to local arguments and variables, and may
+return either one value or no value.
+Function arguments are taken from the stack and local variables are
+initialized to 'none.  These local values are declared in a signature block.
+Functions cannot access values on the stack placed there before the function
+was invoked.
+When a function reaches the end or returns, the top stack value (if any
+has been put there) will be copied to the stack position at the top before
+the function call (minus any arguments).
+
+::
 
     ; Here is a function with two arguments and one local variable.
     [arg1 arg2 | var1 -- ret]
     [
-        ; Function body goes here.
+        ; arg1 & arg2 hold what were the top two items on the stack.
+        ; var1 is none.
+
+        ; TODO: Write this function body.
     ] func :my-function