Added work on making namespaces threadsafe.

src/c/ops/eq.c

@@ -25,8 +25,8 @@
  * @param b another pointer;
  * @return `true` if they are the same, else `false`
  */
-bool eq( struct pso_pointer a, struct pso_pointer b) {
-    return ( a.node == b.node && a.page == b.page && a.offset == b.offset);
+bool eq( struct pso_pointer a, struct pso_pointer b ) {
+    return ( a.node == b.node && a.page == b.page && a.offset == b.offset );
 }
 
 /**
@@ -42,8 +42,8 @@ bool eq( struct pso_pointer a, struct pso_pointer b) {
  * @return `t` if all args are pointers to the same object, else `nil`;
  */
 struct pso_pointer lisp_eq( struct stack_frame *frame,
-                             struct pso_pointer frame_pointer,
-                             struct pso_pointer env ) {
+                            struct pso_pointer frame_pointer,
+                            struct pso_pointer env ) {
     struct pso_pointer result = t;
 
     if ( frame->args > 1 ) {

src/c/ops/eq.h

@@ -12,10 +12,10 @@
 #ifndef __psse_ops_eq_h
 #define __psse_ops_eq_h
 
-bool eq( struct pso_pointer a, struct pso_pointer b);
+bool eq( struct pso_pointer a, struct pso_pointer b );
 
 struct pso_pointer lisp_eq( struct stack_frame *frame,
-                             struct pso_pointer frame_pointer,
-                             struct pso_pointer env );
+                            struct pso_pointer frame_pointer,
+                            struct pso_pointer env );
 
-#endif
+#endif

src/c/ops/eval.c

@@ -26,8 +26,9 @@
  * @param env the evaluation environment.
  * @return struct pso_pointer 
  */
-struct pso_pointer eval_despatch( struct stack_frame *frame, struct pso_pointer frame_pointer,
-           struct pso_pointer env ) {
+struct pso_pointer eval_despatch( struct stack_frame *frame,
+                                  struct pso_pointer frame_pointer,
+                                  struct pso_pointer env ) {
     struct pso_pointer result = frame->arg[0];
 
     // switch ( get_tag_value( result)) {
@@ -52,14 +53,15 @@ struct pso_pointer eval_despatch( struct stack_frame *frame, struct pso_pointer
     return result;
 }
 
-struct pso_pointer lisp_eval( struct stack_frame *frame, struct pso_pointer frame_pointer,
-           struct pso_pointer env ) {
-    struct pso_pointer result = eval_despatch( frame, frame_pointer, env);
+struct pso_pointer lisp_eval( struct stack_frame *frame,
+                              struct pso_pointer frame_pointer,
+                              struct pso_pointer env ) {
+    struct pso_pointer result = eval_despatch( frame, frame_pointer, env );
 
-    if (exceptionp( result)) {
+    if ( exceptionp( result ) ) {
         // todo: if result doesn't have a stack frame, create a new exception wrapping
         // result with this stack frame.
     }
 
     return result;
-}
+}

src/c/ops/truth.c

@@ -0,0 +1,94 @@
+/**
+ *  ops/truth.c
+ *
+ *  Post Scarcity Software Environment: nil? true? not.
+ *
+ *  Functions associated with truthiness.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+/**
+ * @brief true if `p` points to `nil`, else false.
+ *
+ * Note that every node has its own copy of `t` and `nil`, and each instance of 
+ * each is considered equivalent. So we don't check the node when considering
+ * whether `nil` really is `nil`, or `t` really is `t`.
+ * 
+ * @param p a pointer
+ * @return true if `p` points to `nil`.
+ * @return false otherwise.
+ */
+bool nilp( struct pso_pointer p) {
+    return (p.page == 0 && p.offset = 0);
+}
+
+/**
+ * @brief Return `true` if `p` points to `nil`, else `false`.
+ * 
+ * @param p a pointer
+ * @return true  if `p` points to `nil`;
+ * @return false  otherwise.
+ */
+bool not( struct pso_pointer p) {
+    return !nilp( p);
+}
+
+/**
+ * @brief `true` if `p` points to `t`, else `false`.
+ *
+ * Note that every node has its own copy of `t` and `nil`, and each instance of 
+ * each is considered equivalent. So we don't check the node when considering
+ * whether `nil` really is `nil`, or `t` really is `t`.
+ * 
+ * @param p a pointer
+ * @return true if `p` points to `t`.
+ * @return false otherwise.
+ */
+bool truep( struct pso_pointer p) {
+    return (p.page == 0 && p.offset = 1);
+}
+
+/**
+ * @brief return `t` if the first argument in this frame is `nil`, else `t`.
+ * 
+ * @param frame The current stack frame;
+ * @param frame_pointer A pointer to the current stack frame;
+ * @param env the evaluation environment.
+ * @return `t` if the first argument in this frame is `nil`, else `t`
+ */
+pso_pointer lisp_nilp( struct stack_frame *frame,
+                                  struct pso_pointer frame_pointer,
+                                  struct pso_pointer env ){
+    return (nilp(frame->arg[0]) ? t : nil);
+}
+
+/**
+ * @brief return `t` if the first argument in this frame is `t`, else `nil`.
+ * 
+ * @param frame The current stack frame;
+ * @param frame_pointer A pointer to the current stack frame;
+ * @param env the evaluation environment.
+ * @return `t` if the first argument in this frame is `t`, else `nil`.
+ */
+pso_pointer lisp_truep( struct stack_frame *frame,
+                                  struct pso_pointer frame_pointer,
+                                  struct pso_pointer env ){
+    return (truep(frame->arg[0]) ? t : nil);
+}
+
+/**
+ * @brief return `t` if the first argument in this frame is not `nil`, else 
+ * `t`.
+ * 
+ * @param frame The current stack frame;
+ * @param frame_pointer A pointer to the current stack frame;
+ * @param env the evaluation environment.
+ * @return `t` if the first argument in this frame is not `nil`, else `t`.
+ */
+pso_pointer lisp_not( struct stack_frame *frame,
+                                  struct pso_pointer frame_pointer,
+                                  struct pso_pointer env ){
+    return (not(frame->arg[0]) ? t : nil);
+}

src/c/ops/truth.h

@@ -0,0 +1,33 @@
+/**
+ *  ops/truth.h
+ *
+ *  Post Scarcity Software Environment: truth functions.
+ *
+ *  Tests for truth.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#ifndef __psse_ops_truth_h
+#define __psse_ops_truth_h
+
+bool nilp( struct pso_pointer a, struct pso_pointer b );
+
+struct pso_pointer lisp_nilp( struct stack_frame *frame,
+                            struct pso_pointer frame_pointer,
+                            struct pso_pointer env );
+
+bool not( struct pso_pointer a, struct pso_pointer b );
+
+struct pso_pointer lisp_not( struct stack_frame *frame,
+                            struct pso_pointer frame_pointer,
+                            struct pso_pointer env );
+
+bool truep( struct pso_pointer a, struct pso_pointer b );
+
+struct pso_pointer lisp_truep( struct stack_frame *frame,
+                            struct pso_pointer frame_pointer,
+                            struct pso_pointer env );
+
+#endif