From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: =?UTF-8?Q?Cl=c3=a9ment_Pit-Claudel?= Newsgroups: gmane.emacs.devel Subject: A combination of defmacro, functionp, and quoted lambdas yields different results on consecutive evaluations Date: Sat, 17 Feb 2018 11:04:07 -0500 Message-ID: <08190786-14de-a899-f591-a7043c87bebb@gmail.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1518883394 11576 195.159.176.226 (17 Feb 2018 16:03:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 17 Feb 2018 16:03:14 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 To: Emacs developers Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Feb 17 17:03:10 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1en4x5-0002Ms-Mg for ged-emacs-devel@m.gmane.org; Sat, 17 Feb 2018 17:03:03 +0100 Original-Received: from localhost ([::1]:36002 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1en4z7-000720-PH for ged-emacs-devel@m.gmane.org; Sat, 17 Feb 2018 11:05:09 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:38307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1en4yA-0006zg-5J for emacs-devel@gnu.org; Sat, 17 Feb 2018 11:04:11 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1en4y9-00008B-6N for emacs-devel@gnu.org; Sat, 17 Feb 2018 11:04:10 -0500 Original-Received: from mail-qk0-x235.google.com ([2607:f8b0:400d:c09::235]:41902) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1en4y9-000084-2W for emacs-devel@gnu.org; Sat, 17 Feb 2018 11:04:09 -0500 Original-Received: by mail-qk0-x235.google.com with SMTP id h129so7468438qke.8 for ; Sat, 17 Feb 2018 08:04:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:from:subject:message-id:date:user-agent:mime-version :content-language:content-transfer-encoding; bh=EGQvGU+UoM5v3NOXsJyyhmdEE93VVeKP20vBRUuysjw=; b=W4m8NeTiqqWKlKvlR0+CKmVICPdHtz1Q7zQVFmhgRT3BPRMx1HN/vC3mJqa6QSEdpb XLnvh3SMERTU6dB3UT++AeB8sWoLI06GAupiwcmlGIMOFq8hWkHQIJqW0jE2Yn6HSoqZ CvqAaUXn5xwmdA6uouaIxcqaugO+pxhY2VA+qdE6P20RPGKqFb5leEOp4u6m0vqVVDKK 34vyjC5gyc297htgXFHQGiokH6FjTHqeTNT/UqS10R8JSq5YK6eSpYHq/O9YHIOjHUYn 8IZt4t1TF8v6X4kWtZy5O6efOBNP+wbk583XXus/jqWLftmJqnIfuf1dKKrco9dFDj3W 9yFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:from:subject:message-id:date:user-agent :mime-version:content-language:content-transfer-encoding; bh=EGQvGU+UoM5v3NOXsJyyhmdEE93VVeKP20vBRUuysjw=; b=lah7wzzbXPG2uegePRTvpH0C2KdHrt397xL90C22guTPIYYzjwAhIF2w4LdlbVWk2E pJy438g6fgcWY29kVcT66kDgfQGK58QzgZfoTX2zJvrU6UhjL5/i1Ip1VpUlTi4l+Hjb 9vAB+Nykc0E6oTCyvj9qRkRl4dpVyVTLHuXf3b21iT4ipnwfkaVT9Wm1q+ilzc/rr2NT rW0UmtMSGWb1X++vAa3fs1tKxO6b8DfXdOp16ILjIWREKqIoz2Otu6R4OQ63w8LRmdo7 2QRvuML8TaiGUdbTKw4/1DTRoHI9wmyVgTxcNlfuPZ/9vGLj1m86LhGkVFo+BGjAS2NS TOpw== X-Gm-Message-State: APf1xPDV7o2V6o+F0MK5E5rFCw+1xmGcv9oIWoblqyXXfzCN0Pdzxgp7 jpZyOZEG7aZX1AMAEFZZsNCQiqqk X-Google-Smtp-Source: AH8x2265zNSmWgUSpdD5Mhg0HhEPAlHJI4jpIR+iiSIbEMbEcIZ9Ut4YsLtcX9fmShWrQytxNT1IVQ== X-Received: by 10.55.172.1 with SMTP id e1mr10470484qkm.245.1518883448445; Sat, 17 Feb 2018 08:04:08 -0800 (PST) Original-Received: from ?IPv6:2601:184:4180:66e7:b933:6741:71b0:e59a? ([2601:184:4180:66e7:b933:6741:71b0:e59a]) by smtp.gmail.com with ESMTPSA id i63sm3350345qtb.89.2018.02.17.08.04.07 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 17 Feb 2018 08:04:08 -0800 (PST) Content-Language: en-GB X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:400d:c09::235 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:222863 Archived-At: Hey Emacs-devel, We recently ran into a problem in Flycheck that confused us. Evaluating the following twice yields different results on the first evaluation (nil) and on the subsequent ones (t): ;; nil on the first run; t on subsequent ones (progn (defmacro m (f) `(function ,f)) (functionp (m (lambda ())))) Here it is with more info added: ;; "NOK #'(lambda nil)" on the first run; "OK (lambda nil)" on subsequent runs. (progn (defmacro m8 (f) `(function ,f)) (let ((out (m8 (lambda ())))) (message "%s %S" (if (functionp out) "OK" "NOK") out))) This seems to stem from the way macro-evaluation works: running macroexpand-last-sexp before the first evaluation yields this: (progn (defalias 'm (cons 'macro #'(lambda (f) (list 'function f)))) (functionp (m #'(lambda nil)))) … but on subsequent evaluations it yields that: (progn (defalias 'm (cons 'macro #'(lambda (f) (list 'function f)))) (functionp #'(lambda nil))) Is this expected? Did we miss something in the manual about this? Background info: https://github.com/flycheck/flycheck/issues/1398 Thanks! Clément.