Only accept spec compliant dates

[wschella]

Currently, we use JS' builtin Date parser, which is a lot less strict, and as such will accept dates that the spec would not. We should probably follow the spec here. Related to #7.

Spec: The ·lexical space· of dateTime consists of finite-length sequences of characters of the form: '-'? yyyy '-' mm '-' dd 'T' hh ':' mm ':' ss ('.' s+)? (zzzzzz)?, where

• '-'? yyyy is a four-or-more digit optionally negative-signed numeral that represents the year; if more than four digits, leading zeros are prohibited, and '0000' is prohibited (see the Note above (§3.2.7); also note that a plus sign is not permitted);
• the remaining '-'s are separators between parts of the date portion;
• the first mm is a two-digit numeral that represents the month;
• dd is a two-digit numeral that represents the day;
• 'T' is a separator indicating that time-of-day follows;
• hh is a two-digit numeral that represents the hour; '24' is permitted if the minutes and seconds represented are zero, and the dateTime value so represented is the first instant of the following day (the hour property of a dateTime object in the ·value space· cannot have a value greater than 23);
• ':' is a separator between parts of the time-of-day portion;
• the second mm is a two-digit numeral that represents the minute;
• ss is a two-integer-digit numeral that represents the whole seconds;
• '.' s+ (if present) represents the fractional seconds;
• zzzzzz (if present) represents the timezone (as described below).

[rubensworks]

It might even make sense to create some kind of separate xsd-date library, that contains such a new datatype with appropriate methods. I'm sure this would this useful in other projects as well.

[joachimvh]

Wouldn't there already be some existing libraries for this since this is the iso 8601 standard?