WIP: comptime experiments

exercises/075_quiz8.zig

@@ -8,6 +8,8 @@
 // of it.
 //
 const print = @import("std").debug.print;
+const mem = @import("std").mem;
+const fmt = @import("std").fmt;
 
 const TripError = error{ Unreachable, EatenByAGrue };
 
@@ -49,12 +51,47 @@ const Path = struct {
 //
 // Please fill in the body of this function!
 fn makePath(from: *Place, to: *Place, dist: u8) Path {
+    return Path{
+        .from = from,
+        .to = to,
+        .dist = dist,
+    };
+}
 
+fn makePath2(comptime path: []const u8) Path {
+    var it = mem.split(u8, path, "->");
+    var from: []const u8 = it.first();
+    it = mem.split(u8, it.next().?, ":");
+    var to: []const u8 = it.first();
+    var dist: []const u8 = it.next().?;
+    return Path{
+        .from = &@field(@This(), from),
+        .to = &@field(@This(), to),
+        .dist = try fmt.parseInt(u8, dist, 10),
+    };
+}
+
+fn makePath3(comptime path: []const u8) Path {
+    var it = mem.split(u8, path, "->");
+    var from: []const u8 = it.first();
+    var list = it.next().?;
+    var connections_it = mem.split(u8, list[1..(path.len - from.len - 3)], " ");
+
+    while (connections_it.next()) |connect| {
+        var connection_it = mem.split(u8, connect, ":");
+        return Path{
+            .from = &@field(@This(), from),
+            .to = &@field(@This(), connection_it.first()),
+            .dist = try fmt.parseInt(u8, connection_it.next().?, 10),
+        };
+    }
 }
 
 // Using our new function, these path definitions take up considerably less
 // space in our program now!
-const a_paths = [_]Path{makePath(&a, &b, 2)};
+// const a_paths = [_]Path{makePath(&a, &b, 2)};
+const a_paths = [_]Path{makePath2("a->b:2")};
+// const a_paths = makePath3("a->(b:2)");
 const b_paths = [_]Path{ makePath(&b, &a, 2), makePath(&b, &d, 1) };
 const c_paths = [_]Path{ makePath(&c, &d, 3), makePath(&c, &e, 2) };
 const d_paths = [_]Path{ makePath(&d, &b, 1), makePath(&d, &c, 3), makePath(&d, &f, 7) };
@@ -154,6 +191,10 @@ pub fn main() void {
     const start = &a; // Archer's Point
     const destination = &f; // Fox Pond
 
+    // makePath3("a->(b:2 d:3)");
+    var temp: Path = makePath3("a->(b:2)");
+    _ = temp;
+
     // We could either have this:
     //
     //   a.paths = a_paths[0..];