Merge branch 'master' into gh-pages

Conflicts:
	.gitignore

1 files changed, 62 insertions, 0 deletions

diff --git a/go/src/printer/printer.go b/go/src/printer/printer.go
new file mode 100644
index 0000000..1b8e9fe
--- /dev/null
+++ b/go/src/printer/printer.go
@@ -0,0 +1,62 @@
+package printer
+
+import (
+    "fmt"
+    "strings"
+)
+
+import (
+    "types"
+)
+
+func Pr_list(lst []types.MalType, pr bool,
+             start string, end string, join string) string {
+    str_list := make([]string, 0, len(lst))
+    for _, e := range lst {
+        str_list = append(str_list, Pr_str(e, pr))
+    }
+    return start + strings.Join(str_list, join) + end
+}
+
+func Pr_str(obj types.MalType, print_readably bool) string {
+    switch tobj := obj.(type) {
+    case types.List:
+        return Pr_list(tobj.Val, print_readably, "(", ")", " ")
+    case types.Vector:
+        return Pr_list(tobj.Val, print_readably, "[", "]", " ")
+    case types.HashMap:
+        str_list := make([]string, 0, len(tobj.Val)*2)
+        for k, v := range tobj.Val {
+            str_list = append(str_list, Pr_str(k, print_readably))
+            str_list = append(str_list, Pr_str(v, print_readably))
+        }
+        return "{" + strings.Join(str_list, " ") + "}"
+    case string:
+        if strings.HasPrefix(tobj, "\u029e") {
+            return ":" + tobj[2:len(tobj)]
+        } else if print_readably {
+            return `"` + strings.Replace(
+                           strings.Replace(
+                             strings.Replace(tobj,`\`,`\\`, -1),
+                             `"`, `\"`, -1),
+                           "\n", `\n`, -1) + `"`
+        } else {
+            return tobj
+        }
+    case types.Symbol:
+        return tobj.Val
+    case nil:
+        return "nil"
+    case types.MalFunc:
+        return "(fn* " +
+               Pr_str(tobj.Params, true) + " " +
+               Pr_str(tobj.Exp, true) + ")"
+    case func([]types.MalType)(types.MalType, error):
+        return fmt.Sprintf("<function %v>", obj)
+    case *types.Atom:
+        return "(atom " +
+               Pr_str(tobj.Val, true) + ")"
+    default:
+        return fmt.Sprintf("%v", obj)
+    }
+}