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→The Ruby if Statement
''ruby code''<br>
end
In the above outline, the ''expression'' is a logical expression that will evaluate to either true or false. if the expression is true, then the code represented by ''ruby code'' will execute. Otherwise the code is skipped. ''end'' marks the end of the ''if'' statement.
Let's look at an example:
<pre>
if 10 < 20 then
print "10 is less than 20"
end
</pre>
When executed, the script will display the string "10 is less than 20", because the 10 < 20 expression evaluated to true.
If this was any language other than Ruby we would now move on to the next section. Except that this is Ruby we are talking about, so we have more flexibility. Firstly, we can drop the ''then'' keyword and get the same result:
<pre>
if 10 < 20
print "10 is less than 20"
end
</pre>
We can also place the ''if'' after the ''print'' statement, and in doing so, drop the ''end'' statement:
<pre>
print "10 is less than 20" if 10 < 20
</pre>
Similarly, we can place a colon (:) between the ''if'' expression and the statement to be executed:
<pre>
if 10 < 20: print "10 is less than 20" end
</pre>
The expression to be evaluated can also include logical operators. For example:
<pre>
if firstname == "john" && lastname == "smith" then
print "Hello John!"
end
</pre>
== if and elsif ==
