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== OSD600 ==
<u>09/25/2012:</u>
Over the weekend, I wrote a set of about 31 conformance tests for a webvtt parser ([https://github.com/downloads/caitp/webvtt/caitp-cue_settings_tests-09232012.tgz here], more recent ones should be posted [[OSD600/webvtt/cue_settings|here]]).
This is a relatively simple section of the draft, as far as I can tell. It can be illustrated essentially like this (BNF, no state machine diagram here) -- regular expressions have been included in some areas, eg /[0-9]+/. I'm not including the BNF for the other cue-settings here, this is just a start. The main point is that BNF will be helpful for writing scanners and parsers.
<pre>
<webvtt-delimiter> ::= U+0020
| U+0009
<webvtt-delimiters> ::= <webvtt-delimiter>
| <webvtt-delimiters> <webvtt-delimiter>
<vertical-value> ::= "rl"
| "lr"
<vertical-setting> ::= "vertical" ":" <vertical-value>
<line-value-pct> ::= /[0-9]+/ "%"
<line-value-num> ::= /[0-9]+/
| "-" /[0-9]+/
<line-value> ::= <line-value-pct>
| <line-value-num>
<line-setting> ::= "line" ":" <line-value>
<cue-setting> ::= <vertical-setting>
| <line-setting>
| <position-setting>
| <size-setting>
| <align-setting>
<cue-settings> ::= <cue-setting>
| <cue-settings> <webvtt-delimiters> <cue-setting>
</pre>
Some implementation details for the parser:
The spec allows for multiple cue-settings per line (as shown in the BNF), however, the same line setting may not be repeated twice, which would not be caught by a parser generator based on the BNF alone, and would have to be checked for in code.
<u>09/10/2012:</u>
After a few nights of headaches trying to build mozilla-central on windows 7 with Visual Studio 2010, and not getting much in the way of help from IRC, I have finally got a preliminary build together, and am able to attach the VS debugger, which is nice.
Minoo Ziaei blogged a mozconfig which gave me some insight into the build system and helped me to get things working correctly.
I've blogged about it [http://caitpotter.blogspot.ca/2012/09/mozilla-central-built-windows-7-visual.html here]
While I am still investigating exactly how the changes I made to my configuration allowed me to compile without -WX being passed to cl.exe, and will certainly explain this (because it is not obvious at all from the readme or documentation provided by mozilla), I will post about it again when I figure that out completely, for the benefit of other people who are new to the mozilla source.
== Bob ==
[[File:Bob-ross.png|Bob-ross.png|300px]]
