Short format pattern. Currently defined as "HH:mm" but should eventually follow the locale

Long format pattern. Currently defined as "HH:mm:ss" but should eventually follow locale

The round-trippable time pattern, "HH:mm:ss.fffffffff" (nanosecond precision).

The hour of day in the 24-hour clock as w digits, zero-padded; a width of 1 means no padding. Values 00-23.

The double digit hour of day in the 24-hour clock (phour 2); a value 00-23.

The double digit hour of day in the 12-hour clock; a value 01-12. When formatting, the underlying 24-hour value is folded into the 1-12 range (e.g. both 00:00 and 12:00 render as 12). When parsing, the value is combined with an AM/PM designator (pp / ppp) if one is present in the pattern; if no designator is present the value is interpreted as the morning (so 12 parses to midnight).

phh and the AM/PM designators are order independent: each only rewrites its own portion of the hour, so phh <% char ' ' <> ppp and ppp <% char ' ' <> phh both round-trip correctly.

The hour of day in the 12-hour clock, space-padded to two characters (the strftime %l convention), e.g. " 3". Like phh it folds the 24-hour value into 1-12 and combines with an AM/PM designator on parse.

The minute of the hour as w digits, zero-padded; a width of 1 means no padding. Values 00-59.

The double digit minute of the hour (pminute 2); a value 00-59.

The second of the minute as w digits, zero-padded; a width of 1 means no padding. Values 00-59.

The double digit second of the minute (psecond 2); a value 00-59.

Fractional seconds of a fixed width n (1-9 digits, since the underlying resolution is nanoseconds). Formatting shows exactly n zero-padded digits (dropping any finer resolution); parsing reads exactly n digits and scales them back up to nanoseconds (so pfrac 3 parses milliseconds). A width outside 1-9 is a programmer error.

NOTE: this is the first pattern that takes a parameter (all the others are nullary values). The parameterized form was chosen because pf/pF are already taken by the standard date/time patterns and because it covers every width uniformly. If parameterized patterns stay rare we may revisit this; a trailing-zero-trimming variant (the NodaTime F specifier) could also be added later.

12 hour clock time period designation short form; either A or P. See ppp for the long form.

12 hour clock time period designation full form; either AM or PM. When parsing, this only sets whether the hour is in the morning or afternoon; combine with phh to parse a full 12-hour time.

12 hour clock time period designator in the given Locale (e.g. the POSIX AM_STR/PM_STR); the locale-aware counterpart to ppp. NOTE: some locales (e.g. German) leave these designators empty, in which case this pattern cannot round-trip; prefer a 24-hour pattern there.

12 hour clock time period designator using an explicit (am, pm) pair, instead of the built-in AM/PM literals. This is the calendar-agnostic core behind the locale-aware ppp'. Parsing matches either designator case-insensitively (PM tried first); as with ppp it only sets morning/afternoon, so combine it with phh.