Ah, I found out that java bytecode can't contain data literals so the
compiler has to emit a constructor instead.
Also, since the jvm doesn't gc classes there might be confusing memory
leaks if you could embed a closure in evaluated code.
On 9 August 2013 09:13, Christophe Grand wrote:
> You are
You are right, it's beacsue of print-dup. Hence it works only on functions
which aren't closures:
=> (let [a nil x (fn [] a)] (eval [x]))
IllegalArgumentException No matching ctor found for class
user$eval3989$x__3990
Why is emitValue used?
Regular code forms (as returned by the reader) don't us
The Fn case works because print-dup is defined on fns:
user=> (binding [*print-dup* true] (println (fn [] nil)))
#=(user$eval2502$fn__2503. )
nil
user=> (read-string "#=(user$eval2502$fn__2503. )")
#
I still can't figure out why Compiler.emitValue is used though. Am I
right in thinking that cloju
Right now I ca't figure why the fn case is working but the anonyous Var is
failing because the vars are specially handled:
else if(value instanceof Var)
{
Var var = (Var) value;
gen.push(var.ns.name.toString());
gen.push(var.sym.toString());
This actually seems to work for deftypes too:
user=> (deftype Foo [])
user.Foo
user=> (eval (Foo.))
#
user=> (eval [(Foo.)])
[#]
But not for arbitrary objects:
user=> (eval (java.io.StringReader. "foo"))
#
user=> (eval [(java.io.StringReader. "foo")])
CompilerException java.lang.RuntimeExceptio
What if it isn't inside a constant?
user=> (eval `(fn [] ~#'x))
#
user=> (with-local-vars [x nil] (eval `(fn [] ~x)))
CompilerException java.lang.NullPointerException, compiling:(NO_SOURCE_PATH:1:1)
How about functions? These are unreadable but they still eval
correctly inside constants.
user=
The error is caused by the fact that eval sees the var as a constant (or
part of) and tries to serialize the constant.
# is unreadable while #'user/x is that explains teh
difference in behaviour.
On Thu, Aug 8, 2013 at 3:40 PM, Jamie Brandon
wrote:
> This has me stumped:
>
> user=> (with-local-v
This has me stumped:
user=> (with-local-vars [x nil] (eval x))
#
user=> (with-local-vars [x nil] (eval [x]))
CompilerException java.lang.NullPointerException, compiling:(NO_SOURCE_PATH:1:1)
By comparison:
user=> (def x nil)
#'user/x
user=> (eval #'x)
#'user/x
user=> (eval [#'x])
[#'user/x]
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