Moved everything from ops/stack_ops (which were not ops) to payloads/stack.

Added io functions to function_bindings.

Makefile

@@ -52,10 +52,10 @@ coredumps:
 	ulimit -c unlimited
 
 repl: Makefile $(TARGET)
-	$(TARGET) -ps1000 2> tmp/psse.log
+	$(TARGET) -p -s1000 -v1023 2> tmp/psse.log
 
 run: Makefile $(TARGET)
-	$(TARGET) -ps1000v1023 2> tmp/psse.log
+	$(TARGET) -p -s1000 -v1023 2> tmp/psse.log
 
 install: Makefile $(TARGET)
 	cp $(TARGET) ~/bin

src/c/environment/environment.c

@@ -25,7 +25,7 @@
 
 #include "payloads/psse_string.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 #include "payloads/stack.h"
 

src/c/environment/function_bindings.c

@@ -18,6 +18,12 @@
 
 #include "debug.h"
 #include "environment/privileged_keywords.h"
+
+#include "io/io.h"
+#include "io/peek.h"
+#include "io/print.h"
+#include "io/read.h"
+
 #include "memory/node.h"
 #include "memory/pointer.h"
 #include "memory/tags.h"
@@ -35,7 +41,7 @@
 #include "ops/quote.h"
 #include "ops/repl.h"
 #include "ops/reverse.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 
@@ -133,6 +139,54 @@ struct function_data {
 
 /** initialisers for functions */
 struct function_data function_initialisers[] = {
+#ifdef _psse_io_io_h
+	{U"close", U"(close stream): close `stream`.", &lisp_close},
+	{U"open",
+	 U"(open stream), (open stream write?): open `stream`; if `write?` is "
+	 U"present and is non-nil, open for writing, else for reading.",
+	 &lisp_open},
+	{U"slurp",
+	 U"(slurp stream): read the whole contents of this `stream`, "
+	 U"which may "
+	 U"be an open stream open for reading or a URL, into a string, and return "
+	 U"the "
+	 U"string.",
+	 &lisp_slurp},
+#endif
+#ifdef __psse_io_peek_h
+	{U"peek",
+	 U"(peek stream): return the next character which may be read from "
+	 U"`stream`, without removing it.",
+	 &peek},
+#endif
+#ifdef __psse_io_print_h
+	{U"print",
+	 U"(print object), (print object stream) print this `object` in a format "
+	 U"suitable to be read by `read`, q.v.; if `stream` is specified and is a "
+	 U"stream open for writing, to that stream.",
+	 &print},
+	{U"princ",
+	 U"(princ object), (princ object stream) print this `object` in a format "
+	 U"more suited to human readers; if `stream` is specified and is a stream "
+	 U"open for writing, to that stream.",
+	 &print},
+#endif
+#ifdef __psse_io_read_h
+	{U"read",
+	 U"(read stream) read one complete Lisp expression from `stream`, and "
+	 U"return that expression unevaluated.",
+	 &read},
+	{U"read-character",
+	 U"(read_character stream): read a single character from `stream` and "
+	 U"return it.",
+	 &read_character},
+	{U"read_number",
+	 U"(read-number stream): read a number from `stream` and return it.",
+	 &read_number},
+	{U"read_symbol",
+	 U"(read-symbol stream): read a symbol from `stream` and return it.",
+	 &read_symbol},
+#endif
 #ifdef __psse_ops_assoc_h
 	{U"assoc",
 	 U"(assoc key store): search `store` for the value associated with "

src/c/io/io.c

@@ -47,7 +47,7 @@
 
 #include "ops/assoc.h"
 #include "ops/bind.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 
@@ -393,8 +393,7 @@ struct pso_pointer push_back_character( struct pso_pointer c,
  * @param env my environment.
  * @return T if the stream was successfully closed, else nil.
  */
-struct pso_pointer lisp_close( struct pso_pointer frame_pointer,
+struct pso_pointer lisp_close( struct pso_pointer frame_pointer) {
-                               struct pso_pointer env ) {
     struct pso4 *frame = pointer_to_pso4( frame_pointer );
     struct pso_pointer result = nil;
     if ( readp( fetch_arg( frame, 0 ) ) || writep( fetch_arg( frame, 0 ) ) ) {
@@ -591,14 +590,10 @@ URL_FILE *stream_get_url_file( struct pso_pointer s ) {
  *
  * * (open url)
  *
- * @param frame my stack frame.
  * @param frame_pointer a pointer to my stack frame.
- * @param env my environment.
+ * @return a stream open on the URL indicated by the first argument.
- * @return a string of one character, namely the next available character
- * on my stream, if any, else nil.
  */
-struct pso_pointer lisp_open( struct pso_pointer frame_pointer,
+struct pso_pointer lisp_open( struct pso_pointer frame_pointer) {
-                              struct pso_pointer env ) {
     struct pso4 *frame = pointer_to_pso4( frame_pointer );
     struct pso_pointer result = nil;
     if ( stringp( fetch_arg( frame, 0 ) ) ) {
@@ -650,18 +645,13 @@ struct pso_pointer lisp_open( struct pso_pointer frame_pointer,
  * Function: return a string representing all characters from the stream
  * indicated by arg 0; further arguments are ignored.
  *
- * TODO: it should be possible to optionally pass a string URL to this function,
- *
  * * (slurp stream)
  *
- * @param frame my stack frame.
  * @param frame_pointer a pointer to my stack frame.
- * @param env my environment.
+ * @return return a string representing all characters from the stream
- * @return a string of one character, namely the next available character
+ * indicated by arg 0
- * on my stream, if any, else nil.
  */
-struct pso_pointer lisp_slurp( struct pso_pointer frame_pointer,
+struct pso_pointer lisp_slurp( struct pso_pointer frame_pointer) {
-                               struct pso_pointer env ) {
     struct pso4 *frame = pointer_to_pso4( frame_pointer );
     struct pso_pointer result = nil;
     if ( readp( fetch_arg( frame, 0 ) ) ) {

src/c/io/io.h

@@ -11,8 +11,8 @@
 #ifndef __psse_io_io_h
 #define __psse_io_io_h
 
-#include <stdbool.h>
 #include <curl/curl.h>
+#include <stdbool.h>
 
 /*
  * wide characters
@@ -24,12 +24,11 @@
 
 extern CURLSH *io_share;
 
-int initialise_io(  );
+int initialise_io();
-struct pso_pointer initialise_default_streams( struct pso_pointer
+struct pso_pointer initialise_default_streams(struct pso_pointer frame_pointer,
-                                               frame_pointer,
+											  struct pso_pointer env);
-                                               struct pso_pointer env );
 
-#define C_IO_IN  L"*in*"
+#define C_IO_IN L"*in*"
 #define C_IO_OUT L"*out*"
 #define C_IO_LOG L"*log*"
 #define C_IO_READBASE L"*read_base*"
@@ -50,25 +49,19 @@ extern struct pso_pointer lisp_stderr;
 
 extern struct pso_pointer lisp_io_prompt;
 
+URL_FILE *file_to_url_file(FILE *f);
+wint_t url_fgetwc(URL_FILE *input);
+wint_t url_ungetwc(wint_t wc, URL_FILE *input);
 
+struct pso_pointer push_back_character(struct pso_pointer c,
+									   struct pso_pointer r);
 
-URL_FILE *file_to_url_file( FILE * f );
+struct pso_pointer get_default_stream(bool inputp, struct pso_pointer env);
-wint_t url_fgetwc( URL_FILE * input );
-wint_t url_ungetwc( wint_t wc, URL_FILE * input );
 
+URL_FILE *stream_get_url_file(struct pso_pointer s);
 
-struct pso_pointer push_back_character( struct pso_pointer c,
+struct pso_pointer lisp_close(struct pso_pointer frame_pointer);
-                                        struct pso_pointer r );
+struct pso_pointer lisp_open(struct pso_pointer frame_pointer);
-
+struct pso_pointer lisp_slurp(struct pso_pointer frame_pointer);
-struct pso_pointer get_default_stream( bool inputp, struct pso_pointer env );
-
-URL_FILE *stream_get_url_file( struct pso_pointer s );
-
-struct pso_pointer
-lisp_close( struct pso_pointer frame_pointer, struct pso_pointer env );
-struct pso_pointer
-lisp_open( struct pso_pointer frame_pointer, struct pso_pointer env );
-struct pso_pointer
-lisp_slurp( struct pso_pointer frame_pointer, struct pso_pointer env );
 
 #endif

src/c/io/peek.c

@@ -0,0 +1,42 @@
+/**
+ *  io/peek.c
+ *
+ *  Post Scarcity Software Environment: peek.
+ *
+ *  look at the next character on the input stream, without consuming it.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#include <curl/curl.h>
+
+#include "io/fopen.h"
+#include "io/io.h"
+
+#include "memory/node.h"
+#include "memory/pointer.h"
+#include "memory/pso2.h"
+
+#include "payloads/character.h"
+
+/**
+ * @brief look at the next character on the input stream, without consuming it.
+ *
+ * (peek stream)
+ */
+struct pso_pointer peek(struct pso_pointer frame_pointer) {
+	struct pso_pointer result = nil;
+	struct pso_pointer input =
+		pointer_to_pso4(frame_pointer)->payload.stack_frame.arg[0];
+
+	if (readp(input)) {
+		URL_FILE *stream = pointer_to_object(input)->payload.stream.stream;
+		wint_t c = url_fgetwc(stream);
+		url_ungetwc(c, stream);
+
+		result = make_character(frame_pointer, c);
+	}
+	return result;
+}
+

src/c/io/peek.h

@@ -0,0 +1,20 @@
+/**
+ *  io/peek.c
+ *
+ *  Post Scarcity Software Environment: peek.
+ *
+ *  peek basic Lisp objects..This is :bootstrap layer peek; it needs to be 
+ *  able to peek characters, symbols, integers, lists and dotted pairs. I 
+ *  don't think it needs to be able to peek anything else.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#ifndef __psse_io_peek_h
+#define __psse_io_peek_h
+#include <stdbool.h>
+
+struct pso_pointer peek( struct pso_pointer frame_pointer );
+
+#endif

src/c/io/print.c

@@ -44,7 +44,7 @@
 #include "payloads/exception.h"
 #include "payloads/integer.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 
 struct pso_pointer in_write( struct pso_pointer p, URL_FILE * output,
@@ -295,6 +295,8 @@ struct pso_pointer c_write(struct pso_pointer frame_pointer,
 /**
  * @brief Simple print for bootstrap layer.
  *
+ * (print object stream)
+ *
  * @param p pointer to the object to print.
  * @param stream if a pointer to an open write stream, print to there.
  * @return struct pso_pointer `nil`, or an exception if some erroe occurred.

src/c/io/read.c

@@ -40,7 +40,7 @@
 
 #include "ops/assoc.h"
 #include "ops/reverse.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 

src/c/memory/memory.c

@@ -23,11 +23,12 @@
 #include "memory/pso2.h"
 #include "memory/tags.h"
 
-#include "ops/truth.h"
 #include "payloads/exception.h"
+#include "payloads/stack.h"
 
 #include "ops/bind.h"
 #include "ops/string_ops.h"
+#include "ops/truth.h"
 
 /**
  * @brief Freelists for each size class.

src/c/memory/node.c

@@ -22,7 +22,7 @@
 #include "payloads/exception.h"
 
 #include "ops/eq.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 

src/c/memory/pso4.h

@@ -15,7 +15,7 @@
 #include "memory/header.h"
 
 #include "payloads/free.h"
-#include "payloads/stack.h"
+#include "payloads/stack_payload.h"
 
 /**
  * @brief A paged space object of size class 4, 16 words total, 14 words

src/c/ops/assoc.c

@@ -21,7 +21,7 @@
 #include "payloads/stack.h"
 
 #include "ops/eq.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 
 /**

src/c/ops/bind.c

@@ -16,7 +16,7 @@
 #include "memory/pso4.h"
 #include "memory/tags.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 #include "payloads/cons.h"
 #include "payloads/function.h"

src/c/ops/cond.c

@@ -13,7 +13,7 @@
 
 #include "ops/eval_apply.h"
 #include "ops/progn.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 

src/c/ops/dump.c

@@ -23,7 +23,7 @@
 #include "memory/tags.h"
 #include "io/print.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "payloads/lambda.h"
 
 

src/c/ops/eq.c

@@ -19,7 +19,7 @@
 #include "payloads/function.h"
 #include "payloads/integer.h"
 #include "payloads/stack.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 
 /**

src/c/ops/eval_apply.c

@@ -33,7 +33,7 @@
 #include "ops/eval_apply.h"
 #include "ops/progn.h"
 #include "ops/reverse.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"
 

src/c/ops/inspect.c

@@ -18,7 +18,7 @@
 #include "memory/pso4.h"
 #include "memory/tags.h"
 #include "ops/inspect.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 /**
  * Function: dump/

src/c/ops/list_ops.c

@@ -12,7 +12,7 @@
 #include "memory/pso2.h"
 #include "memory/pso4.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 #include "payloads/cons.h"
 #include "payloads/integer.h"

src/c/ops/mapcar.c

@@ -19,7 +19,7 @@
 
 #include "ops/eval_apply.h"
 #include "ops/reverse.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 
 #include "payloads/cons.h"

src/c/ops/progn.c

@@ -17,7 +17,7 @@
 #include "memory/tags.h"
 
 #include "ops/eval_apply.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 #include "payloads/cons.h"
 #include "payloads/stack.h"

src/c/ops/quote.c

@@ -12,7 +12,7 @@
 #include "memory/pointer.h"
 #include "memory/pso4.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 /**
  * @brief Special form: protect an expression from evaluation.

src/c/ops/repl.c

@@ -33,7 +33,7 @@
 
 #include "ops/assoc.h"
 #include "ops/eval_apply.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 
 /**

src/c/ops/reverse.c

@@ -19,7 +19,7 @@
 #include "memory/pso4.h"
 #include "memory/tags.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "payloads/cons.h"
 #include "payloads/exception.h"
 #include "payloads/psse_string.h"

src/c/ops/truth.c

@@ -14,7 +14,7 @@
 #include "memory/node.h"
 #include "memory/pointer.h"
 #include "memory/pso4.h"
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 /**
  * @brief true if `p` points to `nil`, else false.

src/c/payloads/cons.c

@@ -19,7 +19,7 @@
 #include "payloads/cons.h"
 #include "payloads/exception.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/string_ops.h"
 
 /**

src/c/payloads/exception.c

@@ -26,7 +26,7 @@
 
 #include "payloads/exception.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 #include "ops/truth.h"
 #include "payloads/cons.h"
 #include <stdlib.h>

src/c/payloads/psse_string.c

@@ -23,7 +23,7 @@
 #include "ops/string_ops.h"
 #include "payloads/cons.h"
 
-#include "ops/stack_ops.h"
+#include "payloads/stack.h"
 
 
 /**

src/c/payloads/read_stream.c

@@ -12,6 +12,9 @@
 #include <curl/curl.h>
 
 #include "io/fopen.h"
+#include "io/io.h"
+
+#include "memory/node.h"
 #include "memory/pointer.h"
 #include "memory/pso.h"
 #include "memory/pso2.h"

src/c/payloads/stack.c

@@ -21,10 +21,10 @@
 #include "memory/tags.h"
 
 #include "payloads/cons.h"
+#include "payloads/stack.h"
 
 #include "ops/reverse.h"
 #include "ops/list_ops.h"
-#include "ops/stack_ops.h"
 
 /** 
  * @brief The maximum depth of stack before we throw an exception.

src/c/payloads/stack.h

@@ -13,33 +13,7 @@
 #define __psse_payloads_stack_h
 
 #include "memory/pointer.h"
-
+#include "payloads/stack_payload.h"
-/*
- * number of arguments stored in a stack frame
- */
-#define args_in_frame 8
-
-/**
- * A stack frame.
- */
-struct stack_frame_payload {
-    /** the previous frame. */
-    struct pso_pointer previous;
-    /** first 8 arument bindings. */
-    struct pso_pointer arg[args_in_frame];
-    /** list of any further argument bindings. */
-    struct pso_pointer more;
-    /** the function to be called. */
-    struct pso_pointer function;
-  /** the execute-time environment */
-    struct pso_pointer env;
-  /** a list of objects created in the context of this frame */
-    struct pso_pointer locals;
-    /** the number of arguments provided. */
-    uint32_t args;
-    /** the depth of the stack below this frame */
-    uint32_t depth;
-};
 
 /*
  * number of arguments stored in a stack frame

src/c/payloads/stack_payload.h

@@ -0,0 +1,45 @@
+/**
+ *  payloads/stack_payload.h
+ *
+ *  payload struct itself separated out from functions which interrogate it
+ *  to avoid circularity with pso4.
+ *
+ *  Sits in a pso4.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#ifndef __psse_payloads_stack_payload_h
+#define __psse_payloads_stack_payload_h
+
+#include "memory/pointer.h"
+
+/*
+ * number of arguments stored in a stack frame
+ */
+#define args_in_frame 8
+
+/**
+ * A stack frame.
+ */
+struct stack_frame_payload {
+    /** the previous frame. */
+    struct pso_pointer previous;
+    /** first 8 arument bindings. */
+    struct pso_pointer arg[args_in_frame];
+    /** list of any further argument bindings. */
+    struct pso_pointer more;
+    /** the function to be called. */
+    struct pso_pointer function;
+  /** the execute-time environment */
+    struct pso_pointer env;
+  /** a list of objects created in the context of this frame */
+    struct pso_pointer locals;
+    /** the number of arguments provided. */
+    uint32_t args;
+    /** the depth of the stack below this frame */
+    uint32_t depth;
+};
+
+#endif

src/c/psse.c

@@ -27,7 +27,6 @@
 #include "memory/tags.h"
 
 #include "ops/repl.h"
-#include "ops/stack_ops.h"
 #include "ops/string_ops.h"
 #include "ops/truth.h"