Fossil Skins Extra: th1x

TH1 extension functions

Fossil comes with a neat but lightweigh TCL-like language. It can be utilized for other things, but in the GitHub or Stackoverflow themes it's used for pretty interfaces.

The features/*.th1 collections provide a few basic extensions.

Control structures (basic.th1)

Increment a variable
```
++ varname
```
Shorthand if-else:
```
?:  {$x<5}  "true"  {puts "false"}
```
Shorthand info exists
```
isset varname
```
While-loop
```
while {$x < 7} {
   ++ x
}
```

Foreach over lists

set list "aa bb cc dd ee"

foreach var $list {
    puts $var
}

And a switch statement:

switch $x {
    {1} {
        puts "value was 1."
    }
    {zzz} {
        puts "Sleepy value."
    }
    {{default}} {
        puts "Something else."
    }
}

String functions (str.th1)

Shorthand string search (returns either just 1 or 0):
```
str::contains  "/"  "dirname/filename"
```
Return substring position after startindex (the TH1 builtin string first function doesn't yet do that, contrary to its documentation).
```
str::next "/" "http://example.org/this" 10
```
Wrap HTML tags around search terms in a string:
```
str::wrap  $html  "findme"  "<b>"  "</b>"
```

Get directory name from path

str::dirname  "/etc/passwd"    # returns just /etc

Database functions (sql.th1)

To further simplify some of the template features, some basic database functions are included. They're all sql:: prefixed:

sql::allowed $str tests for whitelisted characters. ~~Because the new prepared statements query API is not yet in Fossil mainline, we have to resort to escaping or whitelisting in this case~~. Actually, Fossils TH1 query automatically binds literal $varnames as parameters. Either enclose the query in unparsed {..} curly braces, or escape \$varnames to be parameterized. (So this function is redundant now.)
sql::page_exists $Wiki tests for existence of a wiki page.
sql::file_exists $pathname tests if the filename exists in the repository (must include complete path).
While sql::find_file $basename allows a file to be located anywhere in the directory tree, and then returns its complete path.

User interface / template code (github.th1)

ui::stats returns some variables: $stats_checkins, $stats_files, $stats_tickets, $stats_branches, $stats_developers, $stats_tags, , $stats_releases
u::lang_stats outputs the language bar from fx_stats percentages.
ui::last_commit outputs two table rows, used by the GitHub template file box.
ui::recent_files "" outputs table rows containing the top-level filenames and subdirectories. If a subdirectory name is passed, it will constrain the output to thats contents.
ui::social_links $baseurl outputs facebook/google+/reddit/twitter/etc. links.