The function to share code has long been used.
The function receives some arguments, does something, and returns a result.
function add(a, b) {
return a + b;
}
System.println(add(1, 2)); // 3The function can accept a rest operator only at the last argument like JavaScript.
It is useful for variable arguments.
function toArrayWith3(...a) {
var b = [...a]; // copy
return b + [3];
}
System.println(toArrayWith3(1, 2).join(', ')); // "1, 2, 3"Recursive calling is available, but not supported a tail-recursion optimization.
function fib(n) {
if (n < 3) return n;
return fib(n-2) + fib(n-1);
}
System.println("fib(34) = ", fib(34)); // fib(34) = 9227465You can use a destructuring assignment style in arguments, which is same as declaration statement. The following three styles are available.
- Array Style ... each item in the array will be assigned to a variable in the order.
- Object Key Style ... the value according to a key name will be assigned to the variable of the same name as the key.
- Object Style ... each value will be assigned to the variable bound to each key.
Here is an example.
function func([a, b, , ...c], { x, y }, { x: d, y: { a: e, b: f } }) {
System.println("a = ", a);
System.println("b = ", b);
System.println("c = ", c);
System.println("d = ", d);
System.println("e = ", e);
System.println("f = ", f);
System.println("x = ", x);
System.println("y = ", y);
}
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 300 } });Here is the result.
a = 1
b = 2
c = [4, 5, 6]
d = 20
e = 30
f = 300
x = 10
y = 100
As this is same as assignment and declaration, the pattern matching is available also in an argument.
If a part of variables is a literal, it will be checked if the same value.
And if matching a pattern is failed, the exdeption of NoMatchingPatternException will be raised.
Here is an example.
function func([a, b, , ...c], { x, y }, { x: d, y: { a: e, b: 300 } }) {
System.println("a = ", a);
System.println("b = ", b);
System.println("c = ", c);
System.println("d = ", d);
System.println("e = ", e);
System.println("x = ", x);
System.println("y = ", y);
}
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 300 } });
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 3 } });Here is the result.
a = 1
b = 2
c = [4, 5, 6]
d = 20
e = 30
x = 10
y = 100
Uncaught exception: No one catch the exception.
NoMatchingPatternException: Pattern not matched
Stack Trace Information:
at function func(test.kx:1)
at <main-block>(test.kx:11)
Here is the example of anonymous function. That can be written directly into an expression, and it can be also an argument of a function.
var calc = function(func, a, b) {
return func(a, b);
};
System.println(calc(function(a, b) { return a + b; }, 2, 3)); // 5function fib(n) {
if (n < 3) return n;
return fib(n-2) + fib(n-1);
}
System.println(fib(34)); // => 92274659227465
function fact(a) {
if (a < 1) return 1;
return a * fact(a-1);
}
for (var i = 0; i <= 20; ++i) {
System.println("fact(%{i}) = ", fact(i));
}
System.println("fact(500) = ", fact(500));fact(0) = 1
fact(1) = 1
fact(2) = 2
fact(3) = 6
fact(4) = 24
fact(5) = 120
fact(6) = 720
fact(7) = 5040
fact(8) = 40320
fact(9) = 362880
fact(10) = 3628800
fact(11) = 39916800
fact(12) = 479001600
fact(13) = 6227020800
fact(14) = 87178291200
fact(15) = 1307674368000
fact(16) = 20922789888000
fact(17) = 355687428096000
fact(18) = 6402373705728000
fact(19) = 121645100408832000
fact(20) = 2432902008176640000
fact(500) = 1220136825991110068701238785423046926253574342803192842192413588385845373153881997605496447502203281863013616477148203584163378722078177200480785205159329285477907571939330603772960859086270429174547882424912726344305670173270769461062802310452644218878789465754777149863494367781037644274033827365397471386477878495438489595537537990423241061271326984327745715546309977202781014561081188373709531016356324432987029563896628911658974769572087926928871281780070265174507768410719624390394322536422605234945850129918571501248706961568141625359056693423813008856249246891564126775654481886506593847951775360894005745238940335798476363944905313062323749066445048824665075946735862074637925184200459369692981022263971952597190945217823331756934581508552332820762820023402626907898342451712006207714640979456116127629145951237229913340169552363850942885592018727433795173014586357570828355780158735432768888680120399882384702151467605445407663535984174430480128938313896881639487469658817504506926365338175055478128640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
var n = 10000;
function loop_while(n) {
var v = 0, i = 0;
while (i <= n) {
v += i++;
}
return v;
}
System.println("while(%{n}) = ", loop_while(n));while(10000) = 50005000
var n = 10000;
function loop_for(n) {
var v = 0;
for (var i = 0; i <= n; ++i) {
v += i;
}
return v;
}
System.println("for(%{n}) = ", loop_for(n));for(10000) = 50005000
var n = 10000;
function loop_do_while(n) {
var v = 0, i = 0;
do {
v += i++;
} while (i <= n);
return v;
}
System.println("do_while(%{n}) = ", loop_do_while(n));do_while(10000) = 50005000
var b = 1.7;
function test(a:dbl) {
return a + b;
}
System.println(test(1.5));3.2
var n = 10000;
function loop_while(n) {
var v = 0, i = 0;
LABEL::
while (1) {
while (i <= n) {
if (i == 9) {
++i;
continue;
}
v += i++;
if (i > 10) break LABEL;
}
}
return v;
}
System.println("while(%{n}) = ", loop_while(n));while(10000) = 46
var n = 10000;
function loop_for(n) {
var v = 0;
LABEL::
while (1) {
for (var i = 0; i <= n; ++i) {
if (i == 9) continue;
v += i;
if (i == 10) break LABEL;
}
}
return v;
}
System.println("for(%{n}) = ", loop_for(n));for(10000) = 46
var n = 10000;
function loop_do_while(n) {
var v = 0, i = 0;
LABEL::
while (1) {
do {
if (i == 9) {
++i;
continue;
}
v += i++;
if (i > 10) break LABEL;
} while (i <= n);
}
return v;
}
System.println("do_while(%{n}) = ", loop_do_while(n));do_while(10000) = 46
var b = 100;
var c = 100;
function test() {
var d = 0;
return function (n) {
var a = 100;
try {
try {
a /= d;
} finally {
++b;
}
b %= 9;
} catch (e) {
c = 999;
throw;
} finally {
++b;
}
return a;
};
}
var try_catch = test();
try {
System.println("b = ", b);
System.println(try_catch(10));
} catch (e) {
System.println(e.what());
e.printStackTrace();
} finally {
System.println("b = ", b);
System.println("c = ", c);
}b = 100
Divide by zero
Stack Trace Information:
at <main-block>(test.kx:27)
b = 102
c = 999
function func([a, b, , ...c], { x, y }, { x: d, y: { a: e, b: f } }) {
System.println("a = ", a);
System.println("b = ", b);
System.println("c = ", c);
System.println("d = ", d);
System.println("e = ", e);
System.println("f = ", f);
System.println("x = ", x);
System.println("y = ", y);
}
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 300 } });a = 1
b = 2
c = [4, 5, 6]
d = 20
e = 30
f = 300
x = 10
y = 100
function func([a, b, , ...c], { x, y }, { x: d, y: { a: e, b: 300 } }) {
System.println("a = ", a);
System.println("b = ", b);
System.println("c = ", c);
System.println("d = ", d);
System.println("e = ", e);
System.println("x = ", x);
System.println("y = ", y);
}
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 300 } });
func([1, 2, 3, 4, 5, 6], { x: 10, y: 100 }, { x: 20, y: { a: 30, b: 3 } });a = 1
b = 2
c = [4, 5, 6]
d = 20
e = 30
x = 10
y = 100
Uncaught exception: No one catch the exception.
NoMatchingPatternException: Pattern not matched
Stack Trace Information:
at function func(test.kx:1)
at <main-block>(test.kx:11)