From: Per Bothner <per@bothner.com>
To: Sonny To <son.c.to@gmail.com>
Cc: Kawa mailing list <kawa@sourceware.org>
Subject: Re: using lambda to implement one method interface
Date: Mon, 18 Sep 2017 13:59:00 -0000 [thread overview]
Message-ID: <f75ff3cd-829b-ffdd-3eb1-44b7a2ef5172@bothner.com> (raw)
In-Reply-To: <CAJxjsJsz_NSmCgiX-PFRLFobZ39eW3H_yLWUo9Kp9QbPDC8_Fg@mail.gmail.com>
On 09/18/2017 01:16 AM, Sonny To wrote:
> It seems implementing single method interface using lambda only works
> with methods and not in constructors?
>
> for example, this fails
>
> #|kawa:137|# (java.lang.Thread (lambda ()
> (+ 1 1)))
> #|.....138|# /dev/stdin:137:1: warning - no possibly applicable method
> '<init>/valueOf' in java.lang.Thread
> gnu.mapping.WrongArguments
Yes and no. Method selection uses different code than the code that checks
for type compatibility. It's mostly the same tests, but the former doesn't
handle lambda-to-interface conversion. It would be non-trivial to change that.
However, this works:
(java.lang.Thread (->java.lang.Runnable (lambda () (newline))))
--
--Per Bothner
per@bothner.com http://per.bothner.com/
next prev parent reply other threads:[~2017-09-18 13:59 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-17 15:32 Sonny To
2017-09-17 15:38 ` Sonny To
2017-09-17 15:59 ` Per Bothner
2017-09-17 16:04 ` Sonny To
2017-09-17 16:50 ` Per Bothner
2017-09-17 18:54 ` Sonny To
2017-09-17 20:02 ` Per Bothner
2017-09-18 6:35 ` Sonny To
2017-09-18 8:17 ` Sonny To
2017-09-18 13:59 ` Per Bothner [this message]
2017-09-18 11:22 ` Sudarshan S Chawathe
2017-09-18 14:24 ` Per Bothner
2017-09-18 14:31 ` Sudarshan S Chawathe
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