Please read more from http://docs.eiffel.com/book/solutions/date-time-string-conversion.

                      DATE / TIME to STRING Conversion

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DATE / TIME to STRING format conversion codes

Code 	Description
dd 	day - numeric
[0]dd 	day - numeric (padded with '0' to 2 figures)
ddd 	day - text (3 letters e.g "MON", "TUE")
yyyy 	year - numeric (4 figures)
yy 	year - numeric (2 figures)
mm 	month - numeric
[0]mm 	month - numeric (padded with '0' to 2 figures)
mmm 	month - text (3 letters e.g "DEC", "JAN")
hh 	hour - numeric (24 hour clock scale by default)
[0]hh 	hour - numeric (padded with '0' to 2 figures)
hh12 	hour - numeric (12 hour clock scale)
mi 	minute - numeric
[0]mi 	minute - numeric (padded with '0' to 2 figures)
ss 	seconds - numeric
[0]ss 	seconds - numeric (padded with '0' to 2 figures)
ff<n> 	fractional seconds - numeric (precise to <n> figures)
am 	meridiem indicator. Includes "AM" for ante meridiem times (before noon) and "PM" for post meridiem times (after noon).
':', '/', '-' and ',' 	separators e.g. "03/FEB/08"


These are some examples of output with their associated format code:
Code 				Output
yy/mm/dd 			08/2/3
mmm-[0]dd-yy 			FEB-03-08
dd,mm,yyyy 			3,2,2008
hh-mi-ss 			13-6-32
hh12,mi,ss 			1,6,32
hh12:[0]mi:[0]ss:ff2 am 	1:06:32.25 PM
[0]hh:[0]mi:[0]ss.ff3 		13:06:32.248
[0]mm/dd/yy hh12:mi:ss.ff3 	02/3/08 1:6:32.248 

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