Idioms for error handling with contextual information?

[squeek502]

Previously:

Newbie: idiom to add information to error

This is commonly referred to as the “Diagnostics” pattern. There are several examples in Zig’s stdlib. Here’s one for std.json: std.json.Diagnostics.

Example using diagnostics for error handling with std.json

I can’t seem to find an example of using diagnostics to report error details. For example, I have this code that fails with a SyntaxError, but which line? const std = @import("std"); const Place = struct { lat: f32, long: f32 }; test "json parse" { const parsed = try std.json.parseFromSlice( Place, std.testing.allocator, \\{ \\ "lat": 40.684540, \\ "long": -74.401422, \\} , .{}, ); defer parsed.deinit(); const pla…