X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=TODO;h=ff2a556127c76740e70bece890946b6003212739;hb=5997a66d9b078d75f821eedc9ba615c9df321e98;hp=a3c5981fbbbf7a6f11a4f8d67041c8be49a506a9;hpb=f51558ad815336850db5185d7cebe0478663884f;p=ocaml-bitstring.git

diff --git a/TODO b/TODO
index a3c5981..ff2a556 100644
--- a/TODO
+++ b/TODO
@@ -63,4 +63,74 @@ Major to-do items.
      of functions to be called (at compile time).  However do note
      that the offset in the bitstring is usually not known.
 
-(17) Fix the META file.  Current one is very broken.
+(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).