59 lines
814 B
Dart
59 lines
814 B
Dart
///
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/// functions
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///
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main(List<String> args) {
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var n = add(200, 100);
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print(n);
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var m = minus(200, 100);
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print(m);
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output('Hello');
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func(1, 2, 3);
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func(4, 5);
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func(6);
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print('');
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func2(10, a: 1, b: 2);
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func2(0, b: 3);
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print('');
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fun3(1);
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fun3(1, y: 2);
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}
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int add(int x, int y) {
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return x + y;
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}
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// 函数返回值类型为dynamic
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minus(int x, int y) {
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return x - y;
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}
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// '=>' 等价于 '{return xxxx;}'
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output(var s) => print(s);
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// Optional Parameters
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func(int a, [int b, int c]) {
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print("a is $a");
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print("b is $b");
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print("c is $c");
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}
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// Optional Named Parameters
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func2(int x, {int a, int b}) {
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print("x is $x");
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print("a is $a");
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print("b is $b");
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}
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// Optional Default Parameters
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fun3(int x, {int y = 10}) {
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print("x is $x");
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print("y is $y");
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}
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