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Opa Application Development
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Opa is a functional language. One of its features is that functions are regular values, which means a function may be passed as a parameter or returned as a result. As such, they follow the same naming rules as any other value.
function f(x,y){ // function f with the two parameters x and y
x + y + 1
}
function int f(x,y){ // explicitly indicates the return type
x + y + 1
}You may notice that there is no return inside the body of a function. That's because Opa uses last expression return, which means the last expression of a function is the return value. For example:
function max(x,y){
if(x >= y) x else y
}If x is greater than or equal to y, then x is the last expression and x will be returned; if y is greater than x, then y is the last expression and y will be returned.
Functionalities are usually regrouped into modules; for example:
module M {
x = 1
y = x
function test(){ jlog("testing") }
}We can access the content of a module by...
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