{"id":195,"date":"2007-10-20T21:41:53","date_gmt":"2007-10-21T04:41:53","guid":{"rendered":"https:\/\/dubinko.info\/blog\/2007\/10\/20\/building-a-tokenizer-for-xpath-or-xquery\/"},"modified":"2007-10-20T21:41:53","modified_gmt":"2007-10-21T04:41:53","slug":"building-a-tokenizer-for-xpath-or-xquery","status":"publish","type":"post","link":"https:\/\/dubinko.info\/blog\/2007\/10\/building-a-tokenizer-for-xpath-or-xquery\/","title":{"rendered":"Building a tokenizer for XPath or XQuery"},"content":{"rendered":"

In researching for an XPath 2.0 implementation, I ran across this curious document<\/a> from the W3C. Despite being labeled a Working Draft (as opposed to a Note), it appears to be a one-shot document with no future hope for updates or enhancements.<\/p>\n

In short, it outlines several options for the first stage or two of an XPath 2.0 or XQuery implementation. (Despite the title, it talks about more than just a tokenizer; additionally a parser and a possible intermediate stage). Tokenizing and parsing XPath are significantly more difficult than other languages, because things like this are perfectly legitimate (if useless):<\/p>\n

if(if) then then else else- +-++-**-* instance\r\nof element(*)* * * **---++div- div -div<\/pre>\n
The document tries to standardize on some terminology for various approaches toward dealing with XPath. The remaining bulk of the document sketches out some lexical states that would be useful for one particular implementation approach. I guess the vibrant, thriving throngs of XPath 2.0 developers didn’t see the need for this kind of assistance.<\/p>\n
In short, I didn’t find it terribly useful. Maybe some readers have, though. Feel free to comment below. Subsequent articles here will describe how I approached the problem. Stay sharp! -m<\/p>\n","protected":false},"excerpt":{"rendered":"
In researching for an XPath 2.0 implementation, I ran across this curious document from the W3C. Despite being labeled a Working Draft (as opposed to a Note), it appears to be a one-shot document with no future hope for updates or enhancements. In short, it outlines several options for the first stage or two of…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[22,30,4,32],"tags":[],"class_list":["post-195","post","type-post","status-publish","format-standard","hentry","category-software","category-writing","category-xml","category-xpath"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8eo8l-39","_links":{"self":[{"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/posts\/195","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/comments?post=195"}],"version-history":[{"count":0,"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/posts\/195\/revisions"}],"wp:attachment":[{"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/media?parent=195"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/categories?post=195"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dubinko.info\/blog\/wp-json\/wp\/v2\/tags?post=195"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}