2021-01-31 02:00:32 +01:00
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//
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// A common case for errors is a situation where we're expecting to
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// have a value OR something has gone wrong. Take this example:
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//
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2021-03-12 08:18:41 +01:00
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// var text: Text = getText("foo.txt");
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2021-01-31 02:00:32 +01:00
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//
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2021-03-12 08:18:41 +01:00
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// What happens if getText() can't find "foo.txt"? How do we express
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2021-01-31 02:00:32 +01:00
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// this in Zig?
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//
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2021-02-10 15:35:16 +01:00
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// Zig lets us make what's called an "error union" which is a value
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2021-01-31 02:00:32 +01:00
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// which could either be a regular value OR an error from a set:
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//
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2021-03-12 08:18:41 +01:00
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// var text: MyErrorSet!Text = getText("foo.txt");
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2021-01-31 02:00:32 +01:00
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//
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// For now, let's just see if we can try making an error union!
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//
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const std = @import("std");
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2021-02-15 22:55:44 +01:00
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const MyNumberError = error{TooSmall};
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2021-01-31 02:00:32 +01:00
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pub fn main() void {
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2024-05-27 15:21:28 +02:00
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var my_number: MyNumberError!u8 = 5;
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2021-01-31 02:00:32 +01:00
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// Looks like my_number will need to either store a number OR
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// an error. Can you set the type correctly above?
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my_number = MyNumberError.TooSmall;
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2021-04-04 22:23:27 +02:00
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std.debug.print("I compiled!\n", .{});
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2021-01-31 02:00:32 +01:00
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}
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