Dangle some more LHF. :-)

docs/LHF.md

@@ -1,14 +1,57 @@
 # Low Hanging Fruit
 Some (comparatively :-)) easy tasks for those who want to get involved.
 
-## Work out build stuff
-At the moment, there's nothing really set up for building the Java bit of
-the system. If you've got some ideas on how to sort something out here, go
-for it!
-
 ## String handling
 Some string ops are implemented, but the full list is at:
 
   https://github.com/perl6/nqp/blob/master/src/QAST/Operations.nqp#L1408
 
 Add tests to t/qast_string.t
+
+## Missing positional ops
+Implement and test splice, existspos and deletepos. The splice functionality
+already exists as a repr function, so just needs a new static method adding
+to Ops. Also need an op for existspos, which is implementable in terms of
+elems and <. Note that if the value passed in is negative, it should add the
+element count to it. Finally, add an op for deletepos, which could be done
+in terms of splice.
+
+## QAST::Var Contextuals
+Implement contextual scope of QAST::Var. Involves a little work, since it
+needs additions to QAST::CompilerJAST, as well as a couple of new ops. The
+ops will basically just need to loop looking for the name; the store one
+should throw if it can't find it, whereas the lookup one can return a null.
+Note that StaticCodeRef already has hashes that map lexical names, so the
+information to do name-based lookups is already there, just not yet used.
+
+## Lexical nqp:: ops
+Implement the following:
+
+* getlex
+* getlex_i
+* getlex_n
+* getlex_s
+* bindlex 
+* bindlex_i
+* bindlex_n
+* bindlex_s
+* getlexdyn
+* bindlexdyn
+
+Just add ops; they need to take the ThreadContext (use :tc in QASTCompilerJAST)
+and use the lexical name info as in the contextuals task (this may actually be
+a bit easier).
+
+## sha1 op
+Implement nqp::sha1, which takes a string and returns another string that
+represents its sha1. Can probably draw on an implementation from the Java
+class library.
+
+## Process related opcodes
+Implement nqp::exit (takes integer exit code) and nqp::sleep (takes double
+number of seconds).
+
+## Work out build stuff
+At the moment, there's nothing really set up for building the Java bit of
+the system. If you've got some ideas on how to sort something out here, go
+for it!