Have you written a web application lately? If so, I bet you’ve been using good
old strftime. I use this on every application I write, but the only format
token I ever remember is “%m is for month.” Or is it minute?
You could pop open ri, man, cheat, or For a Good Strftime, but there’s
a fun wrinkle: strftime behaves differently in Ruby 1.8 and 1.9, and the 1.8
version even varies from system to system. For a weird situation like this, you
can’t trust documentation; there’s only one thing that doesn’t lie: code.
You can fire this little script up on your local machine or your server to get a table that looks like the following:
curl -L http://git.io/0QdLVw > time_formats.rb
ruby time_formats.rb
a Tue Thu Sat
b Nov Nov Dec
c Tue Nov 1 00:00:00 2011 Thu Nov 17 00:14:27 2011 Sat Dec 31 23:59:59 2011
d 01 17 31
e 1 17 31
f %f %f %f
g 11 11 11
h Nov Nov Dec
i %i %i %i
j 305 321 365
k 0 0 23
l 12 12 11
m 11 11 12
n
o %o %o %o
p AM AM PM
q %q %q %q
r 12:00:00 AM 12:14:27 AM 11:59:59 PM
s 1320120000 1321506867 1325393999
t
u 2 4 6
v 1-NOV-2011 17-NOV-2011 31-DEC-2011
w 2 4 6
x 11/01/11 11/17/11 12/31/11
y 11 11 11
z -0400 -0500 -0500
A Tuesday Thursday Saturday
B November November December
C 20 20 20
D 11/01/11 11/17/11 12/31/11
E %E %E %E
F 2011-11-01 2011-11-17 2011-12-31
G 2011 2011 2011
H 00 00 23
I 12 12 11
J %J %J %J
K %K %K %K
L 000 599 999
M 00 14 59
N 000000000 599545000 999999998
O %O %O %O
P am am pm
Q %Q %Q %Q
R 00:00 00:14 23:59
S 00 27 59
T 00:00:00 00:14:27 23:59:59
U 44 46 52
V 44 46 52
W 44 46 52
X 00:00:00 00:14:27 23:59:59
Y 2011 2011 2011
Z EDT EST EST
It prints a few different dates so you can tell which is the date and which is the hour, as well as whether or not you’re going to get leading spaces or zeros, or 12-hour vs 24-hour output.
