What will the variables 'roses' and 'violets' contain after the following statements are executed?
roses = "blue" && "red" violets = "blue" and "red" I expected roses = "red", violets = "blue", as the precendece order of operators is:
But the irb shows both of them as "red". Any Explanations?
Don't confuse assigned value and overall value of the expression. Both lines (as whole expressions) evaluate to "red" because there's no short-circuit there and "red" is the last expression evaluated. See for yourself:
roses = "blue" && "red" # => "red" violets = "blue" and "red" # => "red" roses # => "red" violets # => "blue" Going further, let's place some parentheses, according to precedence
violets = "blue" and "red" becomes
(violets = "blue") and "red" becomes
("blue") and "red" becomes
"red" That's how `violets' gets assigned "blue", but the entire expression evaluates to "red".
Keep in mind that
&&and||operator should be used for boolean expressions evaluation,and/or for control flow evaluations. source:-ruby-style-guide&&, and, ||, or all are Short-circuit operators in Ruby. But
orhas lower precedence than||;andhas has lower precedence than&&. source:-Boolean operators in various languages
That said,source:- Operator Precedence Table-
&&and||has higher precedence than=.Thus your expressionroses = "blue" && "red"is actually becomesroses = ("blue" && "red")
=has higher precedence thanandandor.Thus your expressionviolets = "blue" and "red"is actually becomes(violets = "blue") and "red"
