src/iterator.zig


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const std = @import("std");
const iter = @This();

pub fn Iterator(comptime T: type) type {
    return struct{
        const Self = @This();
        items: []const T,
        index: usize = 0,

        pub fn next(self: *Self) ?T {
            if (self.empty()) return null;
            defer self.index += 1;
            return self.items[self.index];
        }

        pub fn current(self: Self) ?T {
            if (self.empty()) return null;
            return self.items[self.index];
        }

        inline fn empty(self: Self) bool {
            if (self.items.len < 1) return true;
            return false;
        }
    };
}

const t = std.testing;

test "initialize iterator" {
    var iterator = Iterator(u8){.items = "Hello World!"};
    for ("Hello World!", 0..) |c,i| {
        try t.expect(c == iterator.current().?);
        try t.expect(c == iterator.next().?);
        try t.expect(c == iterator.items[i]);
    }
}