Paul,
> On 5 Jun 2020, at 15:11, Paul King <[email protected]> wrote:
> We should never throw a VerifyError, so that is a bug.
OK, I'll create an issue for that, or will you? (I guess you'd be able to
describe it much better than me.)
> But you probably don't want to use "this" in a static context. You probably
> just want $q.metaClass or ${getMetaClass()}.
Well they do work, but I believe Groovy, unlike Java, should support static
this properly, thus in a q's static method q.whatever and this.whatever should
be always precisely the same[1]. And for readability and robustness (e.g., when
the code is copied to another class), I would strongly prefer the latter.
Am I wrong, do I miss something here?
And as for the other issue
> You can make _objects protected to overcome the MPE or use a local variable,
> e.g.:
> def localVar = _objects
> 1.times { localVar << it }
Thanks, of both these work-arounds I happen to know; my question is whether the
problem with private fields is the intended behaviour (in which case I must
admit I have missed it in closure documentation), or whether it is a bug which
I should report :)
Thanks a lot!
OC
[1] Agreed, using this might lead someone who is used to an object-oriented
language like Ruby or Smalltalk to believe that it would work properly when
inherited, but it would not, for Java's at best half-OO, half-C++-like-crap.
But that's beside the point here :)
>
> Cheers, Paul.
>
>
> On Fri, Jun 5, 2020 at 9:33 PM OCsite <[email protected] <mailto:[email protected]>>
> wrote:
> And another thing which I don't understand and seems highly suspicious — do I
> just miss something of importance, or is it a bug?
>
> ===
> 127 ocs /tmp> <q.groovy
> class q {
> static main(av) {
> println "my MC is $this.metaClass"
> }
> }
> 128 ocs /tmp> /usr/local/groovy-3.0.4/bin/groovy q
> Caught: java.lang.VerifyError: Bad type on operand stack
> Exception Details:
> Location:
> q.main([Ljava/lang/String;)V @21: getfield
> Reason:
> Type '[Ljava/lang/String;' (current frame, stack[7]) is not assignable to
> 'q'
> Current Frame:
> bci: @21
> flags: { }
> locals: { '[Ljava/lang/String;',
> '[Lorg/codehaus/groovy/runtime/callsite/CallSite;' }
> stack: { 'org/codehaus/groovy/runtime/callsite/CallSite',
> 'java/lang/Class', uninitialized 10, uninitialized 10, '[Ljava/lang/Object;',
> '[Ljava/lang/Object;', integer, '[Ljava/lang/String;' }
> Bytecode:
> 0000000: b800 144c 2b12 2132 1202 bb00 2359 04bd
> 0000010: 0004 5903 2ab4 001c 5305 bd00 2559 0312
> 0000020: 2753 5904 1229 53b7 002c b900 3203 0057
> 0000030: b1
>
> java.lang.VerifyError: Bad type on operand stack
> Exception Details:
> Location:
> q.main([Ljava/lang/String;)V @21: getfield
> Reason:
> Type '[Ljava/lang/String;' (current frame, stack[7]) is not assignable to
> 'q'
> Current Frame:
> bci: @21
> flags: { }
> locals: { '[Ljava/lang/String;',
> '[Lorg/codehaus/groovy/runtime/callsite/CallSite;' }
> stack: { 'org/codehaus/groovy/runtime/callsite/CallSite',
> 'java/lang/Class', uninitialized 10, uninitialized 10, '[Ljava/lang/Object;',
> '[Ljava/lang/Object;', integer, '[Ljava/lang/String;' }
> Bytecode:
> 0000000: b800 144c 2b12 2132 1202 bb00 2359 04bd
> 0000010: 0004 5903 2ab4 001c 5305 bd00 2559 0312
> 0000020: 2753 5904 1229 53b7 002c b900 3203 0057
> 0000030: b1
>
> at
> java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at
> java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
> at
> java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> 129 ocs /tmp>
> ===
>
>> On 27 May 2020, at 23:42, [email protected] <mailto:[email protected]> wrote:
>>
>> 484 ocs /tmp> <q.groovy
>> class q {
>> static main(av) {
>> new Foo().test()
>> }
>> }
>> class Foo extends Root { }
>> class Root {
>> private _objects=[]
>> void test() {
>> println "this is OK"
>> _objects<<'hi'
>> println "this crashes"
>> 1.times { _objects<<it }
>> }
>> }
>> 485 ocs /tmp> /usr/local/groovy-3.0.4/bin/groovy q
>> this is OK
>> this crashes
>> Caught: groovy.lang.MissingPropertyException: No such property: _objects for
>> class: Foo
>> groovy.lang.MissingPropertyException: No such property: _objects for class:
>> Foo
>> at Root$_test_closure1.doCall(q.groovy:13)
>> at Root.test(q.groovy:13)
>> at Root$test.call(Unknown Source)
>> at q.main(q.groovy:3)
>> 486 ocs /tmp>
>>
>
