def timestamp_string
updated_at > created_at ?
"Updated by #{author} at #{updated_at.to_formatted_s(:short)}" :
"Created by #{author} at #{created_at.to_formatted_s(:short)}" :
end
I've not seen the one-line if-then-else statement form like:
<condition> ? <action_to_do_if_true> : <action_to_do_if_false>
expanded into MORE than one line. I just tried it in irb. It works --
SORT OF -- but it's hard to follow. These both work:
true ? 1 : 2
true ?
1 :
2
... generating an output of "1". But you can't leave anything out. So
these generate an error:
true ? 1
true ?
1
.. as do:
true ? 1 :
true ?
1 :
Besides, as Ben notes, they're not clear. So indeed, do it the easy
way:
def timestamp_string
if updated_at > created_at
"Updated by #{author} at
#{updated_at.to_formatted_s(:short)}"
"Created by #{author} at
#{created_at.to_formatted_s(:short)}"
else
"Created by #{author} at
#{created_at.to_formatted_s(:short)}"
end
end
But this won't work either, because methods return only the LAST
assignment statement, unless you include an explicit "return
<expression>". So regardless of the values of updated_at and
created_at, the above would return ONLY the line starting with
"Created by". (Try it in irb.)
Let's try again, eliminating the duplicate assignment while we're at
it. I added an end-of-line character so the strings wouldn't just run
together. And because you can't use the "+=" method unless a variable
has been initialized as a string, number, array, or something similar,
you wind up with something like:
def timestamp_string
s = ""
if updated_at > created_at
s = "Updated by #{author} at
#{updated_at.to_formatted_s(:short)}\n"
end
s += "Created by #{author} at
#{created_at.to_formatted_s(:short)}"
end
If you REALLY wanted, you could shorten this to:
def timestamp_string
updated_at > created_at ? s = "Updated by #{author} at
#{updated_at.to_formatted_s(:short)}\n" : s = ""
s += "Created by #{author} at
#{created_at.to_formatted_s(:short)}"
end
---Jim Gagne---
