* hy/core/language.hy: Adding a simple `identity` function that returns
the argument supplied to it
* docs/language/core.rst: Updated docs with identity function
Sometimes it is better to start with the false condition, sometimes that
makes the code clearer. For that, the (if-not) macro, which simply
reverses the order of the condition blocks, can be of great use.
Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
In the same vein as defmacro-alias, this implements defn-alias /
defun-alias, which does essentially the same thing as defmacro-alias,
but for functions.
Signed-off-by: Gergely Nagy <algernon@balabit.hu>
* hy/core/language.hy:
-Added a simple coll? function that checks whether the given argument
is an iterable and not a string,
- Also replaced the check in `flatten` by coll?
* tests/native_tests/core.hy: Tests updated for checking coll?
This cleans up a number of doc warnings, including a bad
underline for zero?
While there, added a nil? function to match up with the
new nil is None.
Also un-hid myself from coreteam.
Added first iteration of reader macros
Refactored defmacro and defreader
Added test inn hy/tests/lex/test_lex.py
Added new test in hy/tests/native/tests
Added new test in hy/tests/macros.
changed the error given in the dispatch macro and added some handling for missing symbol and invalid characters
Adding to the manual gensym for macros are 2 new
macros, but very literal from the CL in
letoverlambda.
The first is the (with-gensyms ...) macro that
can generate a small set of syms for a macro. Works
something like:
(defmacro adder2 [A B]
(with-gensyms [a b]
`(let [[~a ~A] [~b ~B]]
(+ ~a ~b))))
and ~a and ~b will be replaced with (gensym "a") and
(gensym "b") respectively.
Then the final macro is a new defmacro that will automatically
replace symbols prefaced with "g!" with a new gensym based on the
rest of the symbol. So in this final version of 'nif':
(defmacro/g! nif4 (expr pos zero neg)
`(let [[~g!result ~expr]]
(cond [(pos? ~g!result) ~pos]
[(zero? ~g!result) ~zero]
[(neg? ~g!result) ~neg])))
all uses of ~g!result will be replaced with (gensym "result").
Simple implementation of gensym in Hy.
Returns a new HySymbol.
Usable in macros like:
(defmacro nif [expr pos zero neg]
(let [[g (gensym)]]
`(let [[~g ~expr]]
(cond [(pos? ~g) ~pos]
[(zero? ~g) ~zero]
[(neg? ~g) ~neg]))))
This addresses all the general comments about (gensym), and doesn't
try to implement "auto-gensym" yet. But clearly the macro approach
instead of the pre-processor approach (as described in the
letoverlambda (http://letoverlambda.com/index.cl/guest/chap3.html#sec_5)
is the way to go
The fancypants Hy award goes to Nick for coming up with the quoted
symbol hack for exports. This broke with foo?, since the export string
needs to be is_foo, but using a quoted string will pick up the change
due to it being a Symbol.
Mad clown love for that, @olasd.
This gets rid of the dichotomy between bootstrap.py and macros.hy,
by making both files hy modules.
I added some error checking to make the macros more resilient. The
biggest (user-visible) change is the change in cond, which now only
accepts lists as arguments. Tests updated accordingly.
Closes: #176 (whoops, no more bootstrap)
This rounds out the first pass at a set of core functions, adding
some that were not in the first PR.
From here I'm working on a contrib.seq and contrib.io module to
hold less obvious but maybe interesting native functions that can
move to core if desired.
This should also close out issure #150 asking for some core
functions like these.
