Reworked io functions to take a configurable reader or writer

4 files changed, 68 insertions, 61 deletions

diff --git a/src/interpreter.zig b/src/interpreter.zig
index a947d6f..05c4516 100644
--- a/src/interpreter.zig
+++ b/src/interpreter.zig
@@ -13,19 +13,19 @@ pub const Interpreter = struct {
         self.field.deinit();
         self.allocator.destroy(self);
     }
-    pub fn init(allocator: std.mem.Allocator, reader: anytype, ioFunctions: io.Functions, args: []const []const u8) !*Interpreter {
+    pub fn init(allocator: std.mem.Allocator, fileReader: anytype, args: []const []const u8) !*Interpreter {
         var i = try allocator.create(Interpreter);
         errdefer allocator.destroy(i);
         i.allocator = allocator;
-        i.field = try field.Field.init_from_reader(allocator, reader);
+        i.field = try field.Field.init_from_reader(allocator, fileReader);
         errdefer i.field.deinit();
-        i.pointer = try pointer.Pointer.init(std.testing.allocator, i.field, ioFunctions, args);
+        i.pointer = try pointer.Pointer.init(std.testing.allocator, i.field, args);
         errdefer i.pointer.deinit();
         return i;
     }
-    pub fn run(self: *Interpreter) !i64 {
+    pub fn run(self: *Interpreter, ioContext: anytype) !i64 {
         while (true) {
-            if (try self.pointer.exec()) |ret| {
+            if (try self.pointer.exec(ioContext)) |ret| {
                 if (ret.code) |code| {
                     return code;
                 } else {
diff --git a/src/io.zig b/src/io.zig
index 549711d..5ec3b48 100644
--- a/src/io.zig
+++ b/src/io.zig
@@ -1,42 +1,37 @@
 const std = @import("std");
 
-pub const IOErrors = error{
-    IOError,
-    NotImplemented,
-};
-
-pub const Functions = struct {
-    characterInput: fn () IOErrors!i64,
-    decimalInput: fn () IOErrors!i64,
-    characterOutput: fn (i64) IOErrors!void,
-    decimalOutput: fn (i64) IOErrors!void,
-};
-
-pub const defaultFunctions = Functions{
-    .characterInput = characterInput,
-    .decimalInput = decimalInput,
-    .characterOutput = characterOutput,
-    .decimalOutput = decimalOutput,
-};
-
-fn characterInput() IOErrors!i64 {
-    // TODO
-    return error.NotImplemented;
-}
-
-fn decimalInput() IOErrors!i64 {
-    // TODO
-    return error.NotImplemented;
-}
-
-fn characterOutput(v: i64) IOErrors!void {
-    std.debug.print("{c}", .{@intCast(u8, v)});
-    return;
+pub fn Context(readerType: anytype, writerType: anytype) type {
+    return struct {
+        reader: readerType,
+        writer: writerType,
+        pub fn characterInput(self: @This()) !i64 {
+            var buffer = [_]u8{0};
+            var n = try self.reader.read(buffer[0..]);
+            if (n == 1) {
+                return buffer[0];
+            }
+            return error.IOError;
+        }
+        pub fn decimalInput(self: @This()) !i64 {
+            _ = self;
+            return error.NotImplemented;
+        }
+        pub fn characterOutput(self: @This(), v: i64) !void {
+            try self.writer.print("{c}", .{@intCast(u8, v)});
+            return;
+        }
+        pub fn decimalOutput(self: @This(), v: i64) !void {
+            try self.writer.print("{d}", .{v});
+            return;
+        }
+    };
 }
 
-fn decimalOutput(v: i64) IOErrors!void {
-    std.debug.print("{d}", .{v});
-    return;
+pub fn context(reader: anytype, writer: anytype) Context(@TypeOf(reader), @TypeOf(writer)) {
+    return .{
+        .reader = reader,
+        .writer = writer,
+    };
 }
 
 test "all" {
diff --git a/src/main.zig b/src/main.zig
index ff4f09b..4eb46a3 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -15,10 +15,10 @@ pub fn main() anyerror!void {
     var file = try std.fs.cwd().openFile("mycology/sanity.bf", .{});
     defer file.close();
 
-    var i = try interpreter.Interpreter.init(gpa.allocator(), file.reader(), io.defaultFunctions, args);
+    var i = try interpreter.Interpreter.init(gpa.allocator(), file.reader(), args);
     defer i.deinit();
 
-    std.os.exit(@intCast(u8, try i.run()));
+    std.os.exit(@intCast(u8, try i.run(io.context(std.io.getStdIn().reader(), std.io.getStdOut().writer()))));
 }
 
 test "all" {
@@ -28,7 +28,7 @@ test "sanity" {
     var file = try std.fs.cwd().openFile("mycology/sanity.bf", .{});
     defer file.close();
     const args = [_][]const u8{"sanity"};
-    var i = try interpreter.Interpreter.init(std.testing.allocator, file.reader(), io.defaultFunctions, args[0..]);
+    var i = try interpreter.Interpreter.init(std.testing.allocator, file.reader(), args[0..]);
     defer i.deinit();
-    try std.testing.expectEqual(try i.run(), 0);
+    try std.testing.expectEqual(try i.run(io.context(std.io.getStdIn().reader(), std.io.getStdOut().writer())), 0);
 }
diff --git a/src/pointer.zig b/src/pointer.zig
index 9aae54e..d2d24bb 100644
--- a/src/pointer.zig
+++ b/src/pointer.zig
@@ -23,7 +23,6 @@ pub const Pointer = struct {
     stringMode: bool = false, // string mode flags
     lastCharWasSpace: bool = false,
     ss: *stackStack.StackStack,
-    ioFunctions: io.Functions,
     argv: []const []const u8,
     rand: *std.rand.Random,
 
@@ -31,7 +30,7 @@ pub const Pointer = struct {
         self.ss.deinit();
         self.allocator.destroy(self);
     }
-    fn eval(p: *Pointer, c: i64) pointerErrorType!?pointerReturn {
+    fn eval(p: *Pointer, ioContext: anytype, c: i64) pointerErrorType!?pointerReturn {
         // Returns non nil if the pointer terminated, and a return code if
         // the program should terminate completely
         switch (c) {
@@ -67,9 +66,9 @@ pub const Pointer = struct {
                     p.x = x;
                     p.y = y;
                     if (v != ' ' and v != ';') {
-                        if (v == 'q' or v == '@') return try p.eval(v);
+                        if (v == 'q' or v == '@') return try p.eval(ioContext, v);
                         var i: usize = 0;
-                        while (i < n) : (i += 1) _ = try p.eval(v);
+                        while (i < n) : (i += 1) _ = try p.eval(ioContext, v);
                     }
                 }
             },
@@ -168,11 +167,25 @@ pub const Pointer = struct {
                 const n = p.ss.toss.pop();
                 try p.field.set(v[0] + p.sox, v[1] + p.soy, n);
             },
-            '.' => try p.ioFunctions.decimalOutput(p.ss.toss.pop()),
-            ',' => try p.ioFunctions.characterOutput(p.ss.toss.pop()),
-            '&' => try p.ss.toss.push(try p.ioFunctions.decimalInput()),
-            '~' => try p.ss.toss.push(try p.ioFunctions.characterInput()),
-            // TODO
+            '.' => ioContext.decimalOutput(p.ss.toss.pop()) catch {
+                p.reverse();
+                return null;
+            },
+            ',' => ioContext.characterOutput(p.ss.toss.pop()) catch p.reverse(),
+            '&' => {
+                const n = ioContext.decimalInput() catch {
+                    p.reverse();
+                    return null;
+                };
+                p.ss.toss.push(n) catch p.reverse();
+            },
+            '~' => {
+                const n = ioContext.characterInput() catch {
+                    p.reverse();
+                    return null;
+                };
+                p.ss.toss.push(n) catch p.reverse();
+            },
             'y' => return error.NotImplemented,
             '(' => {
                 const n = p.ss.toss.pop();
@@ -208,7 +221,7 @@ pub const Pointer = struct {
         }
         return null;
     }
-    pub fn exec(self: *Pointer) !?pointerReturn {
+    pub fn exec(self: *Pointer, ioContext: anytype) !?pointerReturn {
         // Advances to the next instruction of the field and executes it
         // Returns non nil if the pointer terminated, and a return code if
         // the program should terminate completely
@@ -233,18 +246,17 @@ pub const Pointer = struct {
                 if (c == ';') jumpingMode = !jumpingMode;
                 c = self.stepAndGet();
             }
-            result = try self.eval(c);
+            result = try self.eval(ioContext, c);
         }
         self.step();
         return result;
     }
-    pub fn init(allocator: std.mem.Allocator, f: *field.Field, ioFunctions: io.Functions, argv: []const []const u8) !*Pointer {
+    pub fn init(allocator: std.mem.Allocator, f: *field.Field, argv: []const []const u8) !*Pointer {
         var p = try allocator.create(Pointer);
         errdefer allocator.destroy(p);
         p.allocator = allocator;
         p.field = f;
         p.ss = try stackStack.StackStack.init(allocator);
-        p.ioFunctions = ioFunctions;
         p.argv = argv;
         p.x = 0;
         p.y = 0;
@@ -328,16 +340,16 @@ test "minimal" {
     var f = try field.Field.init_from_reader(std.testing.allocator, minimal);
     defer f.deinit();
     const argv = [_][]const u8{"minimal"};
-    var p = try Pointer.init(std.testing.allocator, f, io.defaultFunctions, argv[0..]);
+    var p = try Pointer.init(std.testing.allocator, f, argv[0..]);
     defer p.deinit();
-    try std.testing.expectEqual(p.exec(), pointerReturn{});
+    try std.testing.expectEqual(p.exec(io.context(std.io.getStdIn().reader(), std.io.getStdOut().writer())), pointerReturn{});
 }
 test "almost minimal" {
     const minimal = std.io.fixedBufferStream(" @").reader();
     var f = try field.Field.init_from_reader(std.testing.allocator, minimal);
     defer f.deinit();
     const argv = [_][]const u8{"minimal"};
-    var p = try Pointer.init(std.testing.allocator, f, io.defaultFunctions, argv[0..]);
+    var p = try Pointer.init(std.testing.allocator, f, argv[0..]);
     defer p.deinit();
-    try std.testing.expectEqual(p.exec(), pointerReturn{});
+    try std.testing.expectEqual(p.exec(io.context(std.io.getStdIn().reader(), std.io.getStdOut().writer())), pointerReturn{});
 }