Jochen,
On 3. 4. 2016, at 22:29, Jochen Theodorou <[email protected]> wrote:
> On 03.04.2016 17:33, OC wrote:
> [...]
>> ===
>> 6 /tmp> <q.groovy
>> class q {
>> static main(av) {
>> ExpandoMetaClass.enableGlobally()
>> Root.metaClass.static.propertyMissing={ name ->
>> String getter="get${name.capitalize()}"
>> def body={-> "<$name in $delegate>" }
>> delegate.metaClass.static."$getter"=body
>> body.call() // same problem with body(); delegate."$getter"() would
>> work though
>> }
>> println "- ${Root.weird}"
>> }
>> }
>> interface Root {}
>> 7 /tmp> groovy q.groovy
>> Caught: groovy.lang.MissingMethodException: No signature of method:
>> java.io.StringWriter.capitalize() is applicable for argument types: ()
>> values: []
>> groovy.lang.MissingMethodException: No signature of method:
>> java.io.StringWriter.capitalize() is applicable for argument types: ()
>> values: []
>> at q$_main_closure1.doCall(q.groovy:5)
>> at q.main(q.groovy:10)
>> 8 /tmp>
>
> so I misunderstood... it was not, that somehow body was not recognized as
> closure or such, it is that the execution of code inside fails. capitalize()
> is a method on CharSequence, StringWriter is no CharSequence, so the call
> fails. Did you add such a method yourself? if not, you need to convert to
> String first.
Convert what?
I call the capitalize method only once, on the name argument of the
propertyMissing closure. That is/should be always a String, should it not? Or
is there a valid case where this argument would be something else?
Besides the problem disappears if the "body()" or "body.call()" call gets
replaced by "delegate."$getter"()", which is sort of weird, for
delegate."$getter" actually contains the very body closure :-O
It looks like the way the body closure captures the name variable is... weird:
it seems when body.call() is performed, the propertyMissing closure gets called
again, this time with a StringWriter for "name", in a way which is completely
obscure to me:
===
14 /tmp> <q.groovy
class q {
static main(av) {
ExpandoMetaClass.enableGlobally()
Root.metaClass.static.propertyMissing={ String name ->
def body={-> "<$name in $delegate>" }
body.call()
}
println "- ${Root.weird}"
}
}
interface Root {}
15 /tmp> groovy q.groovy
Caught: groovy.lang.MissingMethodException: No signature of method:
q$_main_closure1.doCall() is applicable for argument types:
(java.io.StringWriter) values: [- <weird in ]
...
16 /tmp>
===
Thank you very much and all the best,
OC
