prompt is optional

README.org

@@ -9,7 +9,7 @@ The intent behind this project--beyond learning x86 assembly--is to fully emulat
 * Build
 Currently there are no dependencies for Miharu. To build and run the CLI REPL, simply:
 
-#+begin_src shell
+#+begin_src
   guix shell --pure -m=manifest.scm
   zig build run
 #+end_src

src/main.zig

@@ -17,7 +17,7 @@
 const std = @import("std");
 const mem = @import("memory.zig");
 const cpu_ = @import("cpu.zig");
-
+var long_prompt = false;
 pub fn main() !void {
     var memory = mem.Memory.init();
     var cpu = cpu_.Cpu.init();
@@ -43,7 +43,11 @@ pub fn main() !void {
     , .{});
     var buffer: [256]u8 = undefined;
     while (true) {
-        prompt(&cpu, &memory);
+        if (long_prompt) {
+            promptLong(&cpu, &memory);
+        } else {
+            promptShort();
+        }
         const line = try input.readUntilDelimiterOrEof(&buffer, '\n');
         const clean = std.mem.trim(u8, line.?, " \n\r");
         var it = std.mem.splitSequence(u8, clean, " ");
@@ -52,7 +56,9 @@ pub fn main() !void {
                 break;
             } else if (std.mem.eql(u8, first_argument, "sr")) {
                 try handleSegmentRegisterCommand(&cpu, &it);
-            }
+            } else if (std.mem.eql(u8, first_argument, "prompt")) {
+                try handlePromptCommand(&it);
+            } else if (std.mem.eql(u8, first_argument, "?")) {}
         } else {
             // noop
         }
@@ -64,14 +70,18 @@ pub fn main() !void {
     _ = try output.writeAll("\x1b[?25h");
 }
 
-fn prompt(cpu: *cpu_.Cpu, memory: *mem.Memory) void {
+fn promptShort() void {
+    std.debug.print("> ", .{});
+}
+
+fn promptLong(cpu: *cpu_.Cpu, memory: *mem.Memory) void {
     _ = memory;
     std.debug.print(
         \\
         \\IP : {x:0>8}
         \\EAX: {x:0>8} EBX: {x:0>8} ECX: {x:0>8} EDX: {x:0>8}
         \\ESP: {x:0>8} EBP: {x:0>8} ESI: {x:0>8} EDI: {x:0>8}
-        \\
+        \\> 
     , .{
         cpu.instruction_pointer,
         cpu.registers.get(.EAX),
@@ -84,7 +94,6 @@ fn prompt(cpu: *cpu_.Cpu, memory: *mem.Memory) void {
         cpu.registers.get(.ESI),
         cpu.registers.get(.EDI),
     });
-    std.debug.print("> ", .{});
 }
 
 fn printSr(cpu: *cpu_.Cpu) void {
@@ -104,6 +113,26 @@ fn printSr(cpu: *cpu_.Cpu) void {
     });
 }
 
+fn handlePromptCommand(it: anytype) !void {
+    if (it.next()) |next_argument| {
+        if (std.mem.eql(u8, next_argument, "long")) {
+            long_prompt = true;
+        } else if (std.mem.eql(u8, next_argument, "short")) {
+            long_prompt = false;
+        } else {
+            std.debug.print(
+                \\Invalid argument. Usage: prompt <long|short>
+                \\
+            , .{});
+        }
+    } else {
+        std.debug.print(
+            \\Invalid number of arguments. Usage: prompt <long|short>
+            \\
+        , .{});
+    }
+}
+
 fn handleSegmentRegisterCommand(cpu: *cpu_.Cpu, it: anytype) !void {
     if (it.next()) |_| {
         std.debug.print("Wrong number of arguments.\n", .{});