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-rw-r--r--24_errors4.zig68
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diff --git a/24_errors4.zig b/24_errors4.zig
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--- a/24_errors4.zig
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@@ -1,68 +0,0 @@
-//
-// Using `catch` to replace an error with a default value is a bit
-// of a blunt instrument since it doesn't matter what the error is.
-//
-// Catch lets us capture the error value and perform additional
-// actions with this form:
-//
-// canFail() catch |err| {
-// if (err == FishError.TunaMalfunction) {
-// ...
-// }
-// };
-//
-const std = @import("std");
-
-const MyNumberError = error{
- TooSmall,
- TooBig,
-};
-
-pub fn main() void {
- // The "catch 0" below is just our way of dealing with the fact
- // that makeJustRight() returns a error union (for now).
- var a: u32 = makeJustRight(44) catch 0;
- var b: u32 = makeJustRight(14) catch 0;
- var c: u32 = makeJustRight(4) catch 0;
-
- std.debug.print("a={}, b={}, c={}", .{a,b,c});
-}
-
-// In this silly example we've split the responsibility of making
-// a number just right into four (!) functions:
-//
-// makeJustRight() Calls fixTooBig(), cannot fix any errors.
-// fixTooBig() Calls fixTooSmall(), fixes TooBig errors.
-// fixTooSmall() Calls detectProblems(), fixes TooSmall errors.
-// detectProblems() Returns the number or an error.
-//
-fn makeJustRight(n: u32) MyNumberError!u32 {
- return fixTooBig(n) catch |err| { return err; };
-}
-
-fn fixTooBig(n: u32) MyNumberError!u32 {
- return fixTooSmall(n) catch |err| {
- if (err == MyNumberError.TooBig) {
- return 20;
- }
-
- return err;
- };
-}
-
-fn fixTooSmall(n: u32) MyNumberError!u32 {
- // Oh dear, this is missing a lot! But don't worry, it's nearly
- // identical to fixTooBig() above.
- //
- // If we get a TooSmall error, we should return 10.
- // If we get any other error, we should return that error.
- // Otherwise, we return the u32 number.
- return detectProblems(n) ???
-}
-
-fn detectProblems(n: u32) MyNumberError!u32 {
- if (n < 10) return MyNumberError.TooSmall;
- if (n > 20) return MyNumberError.TooBig;
- return n;
-}
-