From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28742 invoked by alias); 31 Jul 2014 17:47:46 -0000 Mailing-List: contact zsh-workers-help@zsh.org; run by ezmlm Precedence: bulk X-No-Archive: yes List-Id: Zsh Workers List List-Post: List-Help: X-Seq: 32928 Received: (qmail 19770 invoked from network); 31 Jul 2014 17:47:44 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on f.primenet.com.au X-Spam-Level: X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:date:message-id; bh=wrkfrs1u+z/zg2ZTotskeYnHAMoessYZnKt09Pcl9PU=; b=DOCR/D1hRj4Hl1UNCcW3+LoULeOFhfirk4bfFXg+hxKhZzY2QkH2n6kzUPt8S6z6GW EgTzEkvPFWmB3MwXZFZllB8I6FJOT1nlaGAFNz2PZIY/5NwX8EP/10eigUYA0JS6s+Vq DTEBbMgzKY4AIQrT3JOL46/+KRTi2jzxVJ8qZyTReXR2YVhLHwszSQDZL6qmm+Jc+mqo Aq2JWeLt5D3YyWxIs0AHm3r6BXtSdQl30Xf+8NDusLY4LvHyuEvEHNVTPiZkbHtl6jvC SgxUlFoO+86mBepOmtDZF1T+tedidLDEax3qM3/ENxTAJdpjHkUHDWRE88V7Fb+buNk7 /VGQ== X-Received: by 10.194.192.201 with SMTP id hi9mr19581280wjc.28.1406828858767; Thu, 31 Jul 2014 10:47:38 -0700 (PDT) From: Mikael Magnusson To: zsh-workers@zsh.org Subject: PATCH: Add :^ syntax for zipping two arrays Date: Thu, 31 Jul 2014 19:45:39 +0200 Message-Id: <1406828739-14841-1-git-send-email-mikachu@gmail.com> X-Mailer: git-send-email 1.9.0 Any objections to adding this? Comments on the code is also welcome since I'm not at all sure I thought of all the gotchas in paramsubst(), in particular some allocations might be leaking? Not adding tests until any and all comments are incorporated. --- Doc/Zsh/expn.yo | 12 ++++++++++++ Src/subst.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/Doc/Zsh/expn.yo b/Doc/Zsh/expn.yo index ff9f2b1..2fb803a 100644 --- a/Doc/Zsh/expn.yo +++ b/Doc/Zsh/expn.yo @@ -636,6 +636,18 @@ Similar to the preceding subsitution, but in the opposite sense, so that entries present in both the original substitution and as elements of var(arrayname) are retained and others removed. ) +item(tt(${)var(name)tt(:^)var(arrayname)tt(}))( +Zips two arrays, such that the output array is twice as long as the +longest of tt(name) and tt(arrayname), with the elements alternatingly +being picked from them. If one of the input arrays is shorter, then the +input is repeated until all of the other array has been used up. Thus, + +example(a=(1 2 3 4); b=(a b); print ${a:^b}) + +will output `tt(1 a 2 b 3 a 4 b)'. Either or both inputs may be a scalar, +they will be treated as an array of length 1 with the scalar as the only +element. +) xitem(tt(${)var(name)tt(:)var(offset)tt(})) item(tt(${)var(name)tt(:)var(offset)tt(:)var(length)tt(}))( This syntax gives effects similar to parameter subscripting diff --git a/Src/subst.c b/Src/subst.c index d4b68e2..a66ce01 100644 --- a/Src/subst.c +++ b/Src/subst.c @@ -2878,6 +2878,57 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int pf_flags) } break; } + } else if (inbrace && (*s == '^' || *s == Hat)) { + char **zip, **ap, **apsrc; + ++s; + if (*itype_end(s, IIDENT, 0)) { + untokenize(s); + zerr("not an identifier: %s", s); + return NULL; + } + if (vunset) { + if (unset(UNSET)) { + *idend = '\0'; + zerr("%s: parameter not set", idbeg); + return NULL; + } + val = dupstring(""); + } else { + char *sval; + zip = getaparam(s); + if (!zip) { + sval = getsparam(s); + if (sval) + zip = mkarray(sval); + } + if (!isarr) aval = mkarray(val); + if (zip) { + char **out; + int alen, ziplen, outlen, i = 0; + alen = arrlen(aval); + ziplen = arrlen(zip); + outlen = alen > ziplen ? alen : ziplen; + out = zalloc(sizeof(char *) * (2 * outlen + 1)); + while (i < outlen) { + if (copied) + out[i*2] = aval[i % alen]; + else + out[i*2] = ztrdup(aval[i % alen]); + out[i*2+1] = ztrdup(zip[i % ziplen]); + i++; + } + out[i*2] = NULL; + aval = out; + copied = 1; + isarr = 1; + } else { + if (unset(UNSET)) { + zerr("%s: parameter not set", s); + return NULL; + } + val = dupstring(""); + } + } } else if (inbrace && (*s == '|' || *s == Bar || *s == '*' || *s == Star)) { int intersect = (*s == '*' || *s == Star); -- 1.9.0