Editing Module:Road data/strings/doc (section)

===Parser arguments===
When the parser function of [[Module:Road data/parser]] is called, it is passed up to three parameters. The second one is the field to parse, and the last one is a rarely-used option designed for multiple-shield types. The first and most important parameter is a table of arguments collected by the calling module, which generally includes the state, country, or both; the type and number of the route; and a few miscellaneous arguments. This table of arguments forms the basis of the parser's format string syntax.

The table accessible by the strings includes the following entries by default:
* <code>state</code>: The state or province the route is located in.
* <code>country</code>: The country the route is located in. If the country is not passed by the calling module, the parser will attempt to include it.
The above entries are primarily used to find the string module itself, so they should not be a concern for module writers.

* <code>type</code>: The type of the route. This determines the entry of the root table that is used by the parser.
* <code>route</code>: The route "number". This is easily the most important argument for module writers.

The following entries are used less often:
* <code>county</code>: The county the route is located in. This is usually used for county routes in the United States.
* <code>township</code>: This entry is similar in function and utility to the <code>county</code> entry.
* <code>dab</code>: A tag used to disambiguate the link target. This is mostly used for bannered routes in the United States.
* <code>denom</code>: This rare entry is used exclusively for West Virginia county routes.

Parser hooks, which will be described later, can add entries to this table that may be used by strings.