From 42711c11e9a9a1f653821892aa89f96ec5bbb06e Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Thu, 30 Aug 2018 02:26:48 +0200
Subject: [PATCH] Be able to print maps to some degree

Print the number of elements, or nil if it is a nil map.
---
 compiler.go          |  2 ++
 src/runtime/print.go | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/compiler.go b/compiler.go
index 3b78ddd17..b53e5242e 100644
--- a/compiler.go
+++ b/compiler.go
@@ -1277,6 +1277,8 @@ func (c *Compiler) parseBuiltin(frame *Frame, args []ssa.Value, callName string)
 				}
 			case *types.Interface:
 				c.builder.CreateCall(c.mod.NamedFunction("runtime.printitf"), []llvm.Value{value}, "")
+			case *types.Map:
+				c.builder.CreateCall(c.mod.NamedFunction("runtime.printmap"), []llvm.Value{value}, "")
 			case *types.Pointer:
 				ptrValue := c.builder.CreatePtrToInt(value, c.uintptrType, "")
 				c.builder.CreateCall(c.mod.NamedFunction("runtime.printptr"), []llvm.Value{ptrValue}, "")
diff --git a/src/runtime/print.go b/src/runtime/print.go
index e341c0712..fcb09d719 100644
--- a/src/runtime/print.go
+++ b/src/runtime/print.go
@@ -102,7 +102,21 @@ func printitf(msg interface{}) {
 	}
 }
 
+func printmap(m *hashmap) {
+	print("map[")
+	if m == nil {
+		print("nil")
+	} else {
+		print(m.count)
+	}
+	putchar(']')
+}
+
 func printptr(ptr uintptr) {
+	if ptr == 0 {
+		print("nil")
+		return
+	}
 	putchar('0')
 	putchar('x')
 	for i := 0; i < int(unsafe.Sizeof(ptr))*2; i++ {