![](\"https:\/\/i0.wp.com\/www.albertopasca.it\/whiletrue\/wp-content\/uploads\/2018\/08\/flatternOperator.png\")
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Let’s see a simple example just to convince you to use it!<\/p>\n
Percentage calculation<\/h6>\n
Why don’t you use the percentage sign “%<\/strong>” to calculate the percentage?<\/p>\n What do you think of this:<\/p>\n If you like it, you can continue reading!<\/p>\n How works this percentage sign?<\/p>\n New operators are declared at a global level using the\u00a0 This means that your new operator (%) can be used as:<\/p>\n as you prefer.<\/p>\n Example for percentage using POSTFIX<\/strong>:<\/p>\n that’s all. You can use now\u00a05%<\/strong> and get 0.05<\/strong> as value.<\/p>\n Let’s see an example using PREFIX<\/strong>, the square root:<\/p>\n Using operator prefix you can put your symbol before\u00a0your number or your variable.<\/p>\n The last one is the INFIX<\/strong> operator that is used between numbers. Example:<\/p>\n this operator can be used between numbers.<\/p>\n Cool right?<\/p>\n Now, something more interesting about operators. This was the funny part, now the complicated one.<\/p>\n For every operator, we can define the precedence <\/strong>using the keyword Read more also on Apple reference:\u00a0https:\/\/developer.apple.com\/documentation\/swift\/swift_standard_library\/operator_declarations\u00a0<\/a><\/p>\n It’s nice, but is better to do using generics<\/strong>, no?<\/p>\n You can find a recap here:<\/p>\n Swift – Use generics [T] with closures<\/a><\/p><\/blockquote>\nvar<\/span> fivePercent = 5<\/span>%<\/strong>\u2029print<\/span>( <\/span>fivePercent ) \/\/\u00a0<\/span>0.05<\/span><\/pre>\n
\nTL;DR<\/h2>\n
operator<\/span><\/code>\u00a0keyword, and are marked with the\u00a0prefix<\/span><\/code>,\u00a0infix<\/span><\/code>\u00a0or\u00a0postfix<\/span><\/code>\u00a0modifiers:<\/p>\nprefix[postfix, infix]<\/span> operator<\/span> %<\/pre>\n\n
postfix<\/span><\/code> like\u00a05% <\/strong><\/li>\nprefix<\/span><\/code> like\u00a0%5<\/strong><\/li>\ninfix<\/span><\/code> like\u00a0 2%5<\/strong><\/li>\n<\/ul>\npostfix<\/strong> operator %<\/span><\/strong>\u2029postfix<\/span> func<\/span> %<\/strong> (percentage: Int<\/span>) -> Double<\/span> {\u2029\u00a0 \u00a0 <\/span>return<\/span> (Double<\/span>(percentage) \/ 100<\/span>)\u2029}\u2029\u2029var<\/span> fivePercent = 5<\/span>%<\/strong>\u2029print<\/span>( <\/span>fivePercent )<\/span><\/pre>\nprefix operator \u221a<\/span><\/strong>\u2029prefix<\/span> func<\/span> \u221a<\/strong>(lhs: Double<\/span>) -> Double<\/span> {\u2029\u00a0 \u00a0 <\/span>return<\/span> sqrt<\/span>(lhs)\u2029\u2029}\u2029\u2029let<\/span> someVal: Double<\/span> = 25<\/span>\u2029let<\/span> squareRoot = \u221asomeVal<\/span><\/strong>\u2029print<\/span>( <\/span>squareRoot )<\/span><\/pre>\ninfix operator \u2022<\/span><\/strong>\u2029func<\/span> \u2022<\/strong>(lhs: Double<\/span>, rhs: Double<\/span>) -> Double<\/span> {\u2029\u00a0 \u00a0 <\/span>return<\/span> lhs * lhs + rhs * rhs\u2029}\u2029\u2029let<\/span> doubleVal1 = 2.0<\/span>\u2029let<\/span> doubleVal2 = 3.0<\/span>\u2029\u2029let<\/span> squareSum = <\/span>doubleVal1 \u2022 <\/span>doubleVal2<\/strong>\u2029print<\/span>( <\/span>\"squareSum: \\<\/span>(squareSum<\/span>)\" ) \/\/<\/span>squareSum: 13.0<\/strong><\/span><\/pre>\nprecedencegroup<\/h6>\n
precedenceGroup<\/span><\/code>.<\/p>\nprecedencegroup<\/span><\/strong> PowerPrecedence {\u2029\u00a0 \u00a0 <\/span><\/span>associativity: right<\/span>\u2029\u00a0 \u00a0 <\/span>higherThan<\/span>: MultiplicationPrecedence<\/strong>\u2029}\u2029\u2029infix<\/span> operator<\/span> ^^^<\/strong>: PowerPrecedence<\/strong>\u2029func<\/span> ^^^<\/strong> (base: Int<\/span>, power: Int<\/span>) -> Double<\/span> {\u2029\u00a0 \u00a0 <\/span>return<\/span> pow<\/span>(Double<\/span>(base), Double<\/span>(power))\u2029}\u2029\u2029let<\/span> fiveSquared = 5<\/span> ^^^ 2<\/span><\/strong>\u2029print<\/span>( <\/span>fiveSquared ) \/\/<\/span>fiveSquared: 25.0<\/span><\/pre>\n