anchor.diff:  = WORKLOG
  +
  +* use Groovy language specification as case study to find corner cases
   
   == TODO
   
  -* use Groovy language specification as case study to find corner cases
  +* utility method to get % offset of page as y value (option to constrain to bounds)
  +* prevent title-logo-image from spilling to next page
  +* make revision info delimiter configurable in theme
  +* implement per-document title page background image (final fix for #134)
  +
  +* allow theme_font to set line_height (honor this setting from document)
  +  - theme setting for code line height (currently using base_line_height)
  +* remove .to_s calls on color values now that theme normalizes them (perhaps should be a post-load theme procedure)
  +* split prawn_ext/extensions.rb into individual modules and include them
  +* code cleanups (constants and such)
  +* theme keys should be flatted to arbitrary depth
  +* enable line above (or below?) title on title page (file issue)
  +* quote all color values in reference themes
  +* extract regex in ThemeLoader into constant
   * allow pdf-page-layout (portrait || landscape) to be set in document
   * attribute or role to control table shading (all, even, odd) (or call it striped like bootstrap?)
   * make conum glyphs configurable in theme (use reference table to resolve)
  -* make room for large numbers in ordered list (workaround is to set a larger outline_list_indent in theme)
   * add pdf page import support to the image block macro (file issue)
   * do we still need the converter hack in convert_content_for_block? (seems to be needed for admonitions)
   * avoid getting an empty last page (example: colist at bottom of page can cause this)
   * utility to coerce the color value transparent to nil (better handling in general)
  -* quote all color values in reference themes
   * cjk and/or multilingual support
  -* description list term should keep together with content
  -* GhostScript Tiger SVG is reporting incorrect height when embedded; bug in prawn-svg?
  +* description list term should keep together with content (file issue)
  +* GhostScript Tiger SVG is reporting incorrect height when embedded (too much spacing below); bug in prawn-svg?
   * hardbreak in table cell results in extra endline (likely not normalizing cell content)
   * don't create new page if content overflows and we're on the first page
   * parse pdf-page-size syntax 8.5in x 11in (or optional square brackets)
  
positive.code: * make alternating page title position optional (via theme?)
  * BUG: page numbers are off in Clojure Cookbook
  * image in header / banner (need to implement a masthead)
  * do CMYK values work for colors?
  * fix passthrough placeholders that get caught up in syntax highlighting (see https://github.com/asciidoctor/asciidoctor/blob/master/test/blocks_test.rb#L2258-L2277)
  
  * enable pagenums attribute by default (may require changes to how we handle attributes)
  * start page numbering on first page if no title page
  
negative.code: * list bullet in ordered list needs to grow with length of number
  * document how the treetop parser is rebuilt
  * rewrite optimize-pdf using rghost
    - add Optimizer class; wire to cli
  * rework font so we can set actual height, calculate x_height internally (use 1em for spacings)
  * padding top and bottom on content affects height_of calculations (need to review)
  * enable fallback font (Golo guide has problem with License block)
  