X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=TODO;h=ff2a556127c76740e70bece890946b6003212739;hb=5997a66d9b078d75f821eedc9ba615c9df321e98;hp=ecb06207a550c54d12732e10c48ddf0025f34748;hpb=e87f0879fef8e32e7ae7f7103f420c1612f3863f;p=ocaml-bitstring.git

diff --git a/TODO b/TODO
index ecb0620..ff2a556 100644
--- a/TODO
+++ b/TODO
@@ -1,4 +1,4 @@
-$Id: TODO,v 1.5 2008-05-07 14:37:00 rjones Exp $
+$Id$
 Major to-do items.
 
 (1) DONE - In bitmatch operator, use patterns not expressions.
@@ -9,7 +9,7 @@ Major to-do items.
 
 (4) Provide UInt32 and UInt64 types.
 
-(5) Allow for specific offsets and alignment.  Something like this:
+(5) DONE - Allow for specific offsets and alignment.  Something like this:
 
     { start : 16;
       another : 16 : offset(256);   (* location would be 256 bits from start *)
@@ -33,26 +33,104 @@ Major to-do items.
     Make the error locations fine-grained, particularly so they point to
     individual fields, not the whole match.
 
-(10) Cross-module, persistent, named patterns, see:
+(10) DONE - Cross-module, persistent, named patterns, see:
   http://caml.inria.fr/pub/ml-archives/caml-list/2008/04/25992c9c9fa999fe1d35d961dd9917a2.en.html
 
-(11) Runtime endiannness expressions.  The suggested syntax is:
+(11) DONE -
+     Runtime endiannness expressions.  The suggested syntax is:
 
-    { field : len : endianness(expr) }
+    { field : len : endian (expr) }
 
-    where expr would evaluate to something like `BigEndian or
-    `LittleEndian.
+    where expr would evaluate to something like BigEndian or
+    LittleEndian.
 
     There are several protocols around where endianness is only
     determined at runtime, examples are libpcap and TIFF.
 
-(12) More constant field lengths.
+(12) DONE - More constant field lengths.
 
-(13) Implement native endian functions.
+(13) PARTLY DONE - Implement native endian functions.
 
-(14) A proper test suite.
+(14) PARTLY DONE - A proper test suite.
 
-(15) More examples:
+(15) DONE - More examples:
 
     ELF binaries
     GIF images
+
+(16) We now know the offset of the current field relative to the
+     whole match.  This may allow more efficient aligned versions
+     of functions to be called (at compile time).  However do note
+     that the offset in the bitstring is usually not known.
+
+(17) PARTLY DONE - Fix the META file.  Current one is very broken.
+
+(18) DONE - check() qualifier:
+
+     { field : 16 : check (field > 100) }
+
+     The check(expr) qualifier will abort the rest of the match if the
+     expression is false.
+
+(19) DONE - bind() qualifier:
+
+     { field : 16 : bind (field * 3) }
+       ^pattern           ^new value
+
+     The bind(expr) qualifier binds the pattern to a new value,
+     equivalent to doing:
+
+     let field = field * 3 in
+     (* remainder of match *)
+
+     There is a question of whether bind() should run before or
+     after when() [best is probably when() first, then bind()].
+
+(20) DONE - save_offset_to() qualifier:
+
+     { field : 16 : save_offset_to (offset), bind (field - offset) }
+
+     or:
+
+     { field : 16 : save_offset_to (field_offset) } ->
+       printf "the offset of field (%d) is %d\n" field field_offset
+
+     save_offset_to(patt) binds the current match offset to
+     the variable, for later use within bind(), when() or
+     any later parts of the match.
+
+(21) derive() so you can add your own variable decls:
+
+     { field : 32 : derive (field_as_int, Int32.to_int field) }
+
+     This would add a let derivation, equivalent to:
+
+     let field_as_int = Int32.to_int field
+
+     allowing you to use both the original field and field_as_int
+     as variables.
+
+     Note you can do this clumsily using bind():
+
+     { field : 32 : bind (field, Int32.to_int field) }
+
+     which redefines 'field' as a pair of (old value, derived value).
+
+(22) Allow constant 0 to be used in constructors to mean a zero-length
+     bitstring of the right length, eg:
+
+     BITSTRING { 0 : 32*8 : bitstring }
+
+     which would be equivalent to:
+
+     BITSTRING { zeroes_bitstring (32*8) : 32*8 : bitstring }
+
+(23) Add predicate Bitstring.is_zero_bitstring : bitstring -> bool
+
+(24) Add a function to turn bitstrings into printable strings.
+
+(25) Folding over bitstrings.  A narrow usage for this is to generate
+     checksums and hashes, where usually you want to fold over every
+     8/16/32-bit word.  So a set of functions which just enabled this
+     would be useful.  (However you still need le/be/ne variations so
+     it involves at least 7 functions).