MLKCons, MLKSymbol: Override -descriptionForLisp.

4 files changed, 36 insertions, 0 deletions

diff --git a/MLKCons.h b/MLKCons.h
index c727c39..d343e3f 100644
--- a/MLKCons.h
+++ b/MLKCons.h
@@ -34,5 +34,10 @@
 -(void) setCar:(id)value;
 -(void) setCdr:(id)value;
 
+-(NSString *)bareDescriptionForLisp;  // description without
+                                      // parentheses, for internal use
+                                      // only
+-(NSString *)descriptionForLisp;
+
 -(void) dealloc;
 @end
diff --git a/MLKCons.m b/MLKCons.m
index fbfecb7..aee322a 100644
--- a/MLKCons.m
+++ b/MLKCons.m
@@ -18,6 +18,8 @@
 
 #import "MLKCons.h"
 
+#import <Foundation/NSString.h>
+
 
 @implementation MLKCons
 +(MLKCons*) cons:(id)car with:(id)cdr
@@ -54,6 +56,25 @@
   ASSIGN (_cdr, value);
 }
 
+-(NSString *)bareDescriptionForLisp
+{
+  if (!_cdr)
+    return [NSString stringWithFormat:@"%@", [_car descriptionForLisp]];
+  else if (![_cdr isKindOfClass:[MLKCons class]])
+    return [NSString stringWithFormat:@"%@ %@",
+                     [_car descriptionForLisp],
+                     [_cdr bareDescriptionForLisp]];
+  else
+    return [NSString stringWithFormat:@"%@ . %@",
+                     [_car descriptionForLisp],
+                     [_cdr descriptionForLisp]];
+}
+
+-(NSString *)descriptionForLisp
+{
+  return [NSString stringWithFormat:@"(%@)", [self bareDescriptionForLisp]];
+}
+
 -(void) dealloc
 {
   RELEASE (_car);
diff --git a/MLKSymbol.h b/MLKSymbol.h
index 6fe3eb6..82526d2 100644
--- a/MLKSymbol.h
+++ b/MLKSymbol.h
@@ -33,5 +33,7 @@
 -(MLKPackage *) homePackage;
 -(void) setHomePackage:(MLKPackage *)aPackage;
 
+-(NSString *)descriptionForLisp;
+
 -(void) dealloc;
 @end
diff --git a/MLKSymbol.m b/MLKSymbol.m
index 3443e37..42a7141 100644
--- a/MLKSymbol.m
+++ b/MLKSymbol.m
@@ -18,6 +18,8 @@
 
 #import "MLKSymbol.h"
 
+#import <Foundation/NSString.h>
+
 
 @implementation MLKSymbol
 -(MLKSymbol *) initWithName:(id)aName package:(id)aPackage
@@ -43,6 +45,12 @@
   ASSIGN (homePackage, aPackage);
 }
 
+-(NSString *)descriptionForLisp
+{
+  // FIXME: This is wrong in more than one way.
+  return [NSString stringWithFormat:@"|%@|", name];
+}
+
 -(void) dealloc
 {
   RELEASE (name);