{"id":267,"date":"2011-09-23T10:26:00","date_gmt":"2011-09-23T14:26:00","guid":{"rendered":"http:\/\/irreal.org\/blog\/?p=267"},"modified":"2011-12-26T18:00:40","modified_gmt":"2011-12-26T23:00:40","slug":"xahs-emacs-quiz","status":"publish","type":"post","link":"https:\/\/irreal.org\/blog\/?p=267","title":{"rendered":"Xah’s Emacs Quiz"},"content":{"rendered":"\n

Xah Lee has another Emacs challenge<\/a>. This time, it’s to replace entries of the form <\/p>\n

<tr<\/span>><td<\/span>>pound<\/td<\/span>><td<\/span>>&#163;<\/td<\/span>><td<\/span>>pound sign, U+00A3<\/td<\/span>><\/tr<\/span>>\r\n<\/pre>\n
 with entries like this: <\/p>\n
<tr<\/span>><td<\/span>>pound<\/td<\/span>>£<td<\/span>>pound sign, U+00A3<\/td<\/span>><\/tr<\/span>>\r\n<\/pre>\n
 This is, presumably, a small tweaking of Lee’s very useful page on HTML\/XML Entities<\/a> that I’ve written about before<\/a>. <\/p>\n
 It would be reasonably easy to do this by writing some Emacs Lisp but I wanted to see if I could do it interactively. It turns out to be pretty simple using query-replace-regexp<\/code>. The secret is to use \\,<\/code> expr<\/i> as the replacement string in query-replace-regexp<\/code>. With that replacement string, when the regular expression is matched expr<\/i> is called to provide the replacement. I used <\/p>\n
&#\\([0-9]+\\);<\/span>\r\n<\/pre>\n
 as the regular expression and <\/p>\n
\\,(format \"%c\"<\/span> \\#1)\r\n<\/pre>\n
 as the replace string. The \\#1<\/code> takes the first subgroup and converts it to a number. Then the rest of the format<\/code> statement delivers that unicode character as the replacement text. <\/p>\n
 The careful reader will note that this doesn’t give quite what Lee asked for because the <td>...<\/td><\/code> tags are still there. I’m guessing that Lee really wanted them there but if not, it’s easy to get rid of them by using <\/p>\n
<td>&#\\([0-9]+\\);<\/span><\/td><\/span>\r\n<\/pre>\n
 as the regular expression. <\/p>\n","protected":false},"excerpt":{"rendered":"
Xah Lee has another Emacs challenge. This time, it’s to replace entries of the form <tr><td>pound<\/td><td>&#163;<\/td><td>pound sign, U+00A3<\/td><\/tr> with entries like this: <tr><td>pound<\/td>£<td>pound sign, U+00A3<\/td><\/tr> This is, presumably, a small tweaking of Lee’s very useful page on HTML\/XML Entities that … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[18],"class_list":["post-267","post","type-post","status-publish","format-standard","hentry","category-general","tag-emacs"],"_links":{"self":[{"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/267","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=267"}],"version-history":[{"count":6,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/267\/revisions"}],"predecessor-version":[{"id":472,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/267\/revisions\/472"}],"wp:attachment":[{"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=267"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=267"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/irreal.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=267"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}