1 files changed, 180 insertions, 44 deletions

diff --git a/src/core-commands.c b/src/core-commands.c
index 7222a9f..2ccb8ec 100644
--- a/src/core-commands.c
+++ b/src/core-commands.c
@@ -67,6 +67,23 @@ gboolean teco_state_command_process_edit_cmd(teco_machine_main_t *ctx, teco_mach
 		##__VA_ARGS__ \
 	)
 
+/**
+ * @class TECO_DEFINE_STATE_START
+ * @implements TECO_DEFINE_STATE_COMMAND
+ * @ingroup states
+ *
+ * Base state for everything where a new command can begin
+ * (the start state itself and all lookahead states).
+ */
+#define TECO_DEFINE_STATE_START(NAME, ...) \
+	TECO_DEFINE_STATE_COMMAND(NAME, \
+		.end_of_macro_cb = NULL, /* Allowed at the end of a macro! */ \
+		.is_start = TRUE, \
+		.keymacro_mask = TECO_KEYMACRO_MASK_START | TECO_KEYMACRO_MASK_CASEINSENSITIVE, \
+		##__VA_ARGS__ \
+	)
+
+static teco_state_t *teco_state_start_input(teco_machine_main_t *ctx, gunichar chr, GError **error);
 static teco_state_t *teco_state_control_input(teco_machine_main_t *ctx, gunichar chr, GError **error);
 static teco_state_t *teco_state_ctlc_control_input(teco_machine_main_t *ctx, gunichar chr, GError **error);
 
@@ -543,34 +560,173 @@ teco_state_start_cmdline_pop(teco_machine_main_t *ctx, GError **error)
 	g_set_error_literal(error, TECO_ERROR, TECO_ERROR_CMDLINE, "");
 }
 
-/*$ "=" print
- * <n>= -- Show value as message
+/**
+ * Print number from stack in the given radix.
+ *
+ * It must be popped manually, so we can call it multiple times
+ * on the same number.
+ */
+static gboolean
+teco_print(guint radix, GError **error)
+{
+	if (!teco_expressions_eval(FALSE, error))
+		return FALSE;
+	if (!teco_expressions_args()) {
+		teco_error_argexpected_set(error, "=");
+		return FALSE;
+	}
+	/*
+	 * FIXME: There should be a raw output function,
+	 * also to allow output without trailing LF.
+	 * Perhaps repurpose teco_expressions_format().
+	 */
+	const gchar *fmt = "%" TECO_INT_MODIFIER "d";
+	switch (radix) {
+	case 8:  fmt = "%" TECO_INT_MODIFIER "o"; break;
+	case 16: fmt = "%" TECO_INT_MODIFIER "X"; break;
+	}
+	teco_interface_msg(TECO_MSG_USER, fmt, teco_expressions_peek_num(0));
+	return TRUE;
+}
+
+/*$ "=" "==" "===" print
+ * <n>= -- Print integer as message
+ * <n>==
+ * <n>===
  *
  * Shows integer <n> as a message in the message line and/or
  * on the console.
- * It is currently always formatted as a decimal integer and
- * shown with the user-message severity.
+ * One \(lq=\(rq formats the integer as a signed decimal number,
+ * \(lq==\(rq formats as an unsigned octal number and
+ * \(lq===\(rq as an unsigned hexadecimal number.
+ * It is logged with the user-message severity.
  * The command fails if <n> is not given.
+ *
+ * A noteworthy quirk is that \(lq==\(rq and \(lq===\(rq
+ * will print 2 or 3 numbers in succession when executed
+ * from interactive mode at the end of the command line
+ * in order to guarantee immediate feedback.
+ *
+ * If you want to print multiple values from the stack,
+ * you have to put the \(lq=\(rq into a pass-through loop
+ * or separate the commands with whitespace.
  */
-/**
- * @todo perhaps care about current radix
- * @todo colon-modifier to suppress line-break on console?
+/*
+ * In order to imitate TECO-11 closely, we apply the lookahead
+ * strategy -- `=` and `==` are not executed immediately but only
+ * when a non-`=` character is parsed (cf. `$$` and `^C^C`).
+ * However, this would be very annoying during interactive
+ * execution, therefore we still print the number immediately
+ * and perhaps multiple times:
+ * Typing `===` prints the number first in decimal,
+ * then octal and finally in hexadecimal.
+ * This won't happen e.g. in a loop that is closed on the command-line.
+ *
+ * FIXME: Support colon-modifier to suppress line-break on console.
  */
-static void
-teco_state_start_print(teco_machine_main_t *ctx, GError **error)
+TECO_DECLARE_STATE(teco_state_print_decimal);
+TECO_DECLARE_STATE(teco_state_print_octal);
+
+static gboolean
+teco_state_print_decimal_initial(teco_machine_main_t *ctx, GError **error)
 {
-	if (!teco_expressions_eval(FALSE, error))
-		return;
-	if (!teco_expressions_args()) {
-		teco_error_argexpected_set(error, "=");
-		return;
+	if (ctx->flags.mode > TECO_MODE_NORMAL || !teco_cmdline_is_executing(ctx))
+		return TRUE;
+	/*
+	 * Interactive invocation:
+	 * don't yet pop number as we may have to print it repeatedly
+	 */
+	return teco_print(10, error);
+}
+
+static teco_state_t *
+teco_state_print_decimal_input(teco_machine_main_t *ctx, gunichar chr, GError **error)
+{
+	if (chr == '=')
+		return &teco_state_print_octal;
+
+	if (ctx->flags.mode == TECO_MODE_NORMAL) {
+		if (!teco_cmdline_is_executing(ctx) && !teco_print(10, error))
+			return NULL;
+		teco_expressions_pop_num(0);
 	}
-	teco_int_t v;
-	if (!teco_expressions_pop_num_calc(&v, teco_num_sign, error))
-		return;
-	teco_interface_msg(TECO_MSG_USER, "%" TECO_INT_FORMAT, v);
+	return teco_state_start_input(ctx, chr, error);
+}
+
+/*
+ * Due to the deferred nature of `=`,
+ * it is valid to end in this state as well.
+ */
+static gboolean
+teco_state_print_decimal_end_of_macro(teco_machine_main_t *ctx, GError **error)
+{
+	if (teco_cmdline_is_executing(ctx) || ctx->flags.mode > TECO_MODE_NORMAL)
+		return TRUE;
+	if (!teco_print(10, error))
+		return FALSE;
+	teco_expressions_pop_num(0);
+	return TRUE;
+}
+
+TECO_DEFINE_STATE_START(teco_state_print_decimal,
+	.initial_cb = (teco_state_initial_cb_t)teco_state_print_decimal_initial,
+	.end_of_macro_cb = (teco_state_end_of_macro_cb_t)
+	                   teco_state_print_decimal_end_of_macro
+);
+
+static gboolean
+teco_state_print_octal_initial(teco_machine_main_t *ctx, GError **error)
+{
+	if (ctx->flags.mode > TECO_MODE_NORMAL || !teco_cmdline_is_executing(ctx))
+		return TRUE;
+	/*
+	 * Interactive invocation:
+	 * don't yet pop number as we may have to print it repeatedly
+	 */
+	return teco_print(8, error);
+}
+
+static teco_state_t *
+teco_state_print_octal_input(teco_machine_main_t *ctx, gunichar chr, GError **error)
+{
+	if (chr == '=') {
+		if (ctx->flags.mode == TECO_MODE_NORMAL) {
+			if (!teco_print(16, error))
+				return NULL;
+			teco_expressions_pop_num(0);
+		}
+		return &teco_state_start;
+	}
+
+	if (ctx->flags.mode == TECO_MODE_NORMAL) {
+		if (!teco_cmdline_is_executing(ctx) && !teco_print(8, error))
+			return NULL;
+		teco_expressions_pop_num(0);
+	}
+	return teco_state_start_input(ctx, chr, error);
+}
+
+/*
+ * Due to the deferred nature of `==`,
+ * it is valid to end in this state as well.
+ */
+static gboolean
+teco_state_print_octal_end_of_macro(teco_machine_main_t *ctx, GError **error)
+{
+	if (teco_cmdline_is_executing(ctx) || ctx->flags.mode > TECO_MODE_NORMAL)
+		return TRUE;
+	if (!teco_print(8, error))
+		return FALSE;
+	teco_expressions_pop_num(0);
+	return TRUE;
 }
 
+TECO_DEFINE_STATE_START(teco_state_print_octal,
+	.initial_cb = (teco_state_initial_cb_t)teco_state_print_octal_initial,
+	.end_of_macro_cb = (teco_state_end_of_macro_cb_t)
+	                   teco_state_print_octal_end_of_macro
+);
+
 /*$ A
  * [n]A -> code -- Get character code from buffer
  * -A -> code
@@ -651,6 +807,7 @@ teco_state_start_input(teco_machine_main_t *ctx, gunichar chr, GError **error)
 		          .modifier_colon = 1},
 		['X']  = {&teco_state_copytoqreg,
 		          .modifier_at = TRUE, .modifier_colon = 1},
+		['=']  = {&teco_state_print_decimal},
 
 		/*
 		 * Arithmetics
@@ -703,7 +860,6 @@ teco_state_start_input(teco_machine_main_t *ctx, gunichar chr, GError **error)
 		          .modifier_colon = 1},
 		['D']  = {&teco_state_start, teco_state_start_delete_chars,
 		          .modifier_colon = 1},
-		['=']  = {&teco_state_start, teco_state_start_print},
 		['A']  = {&teco_state_start, teco_state_start_get}
 	};
 
@@ -899,11 +1055,7 @@ teco_state_start_input(teco_machine_main_t *ctx, gunichar chr, GError **error)
 	                                          teco_ascii_toupper(chr), error);
 }
 
-TECO_DEFINE_STATE_COMMAND(teco_state_start,
-	.end_of_macro_cb = NULL, /* Allowed at the end of a macro! */
-	.is_start = TRUE,
-	.keymacro_mask = TECO_KEYMACRO_MASK_START | TECO_KEYMACRO_MASK_CASEINSENSITIVE
-);
+TECO_DEFINE_STATE_START(teco_state_start);
 
 /*$ "F<" ":F<"
  * F< -- Go to loop start or jump to beginning of macro
@@ -1787,14 +1939,8 @@ teco_state_escape_end_of_macro(teco_machine_t *ctx, GError **error)
 	return teco_expressions_discard_args(error);
 }
 
-TECO_DEFINE_STATE_COMMAND(teco_state_escape,
-	.end_of_macro_cb = teco_state_escape_end_of_macro,
-	/*
-	 * The state should behave like teco_state_start
-	 * when it comes to function key macro masking.
-	 */
-	.is_start = TRUE,
-	.keymacro_mask = TECO_KEYMACRO_MASK_START | TECO_KEYMACRO_MASK_CASEINSENSITIVE
+TECO_DEFINE_STATE_START(teco_state_escape,
+	.end_of_macro_cb = teco_state_escape_end_of_macro
 );
 
 /*
@@ -1827,18 +1973,8 @@ teco_state_ctlc_initial(teco_machine_main_t *ctx, GError **error)
 	return TRUE;
 }
 
-TECO_DEFINE_STATE_COMMAND(teco_state_ctlc,
-	.initial_cb = (teco_state_initial_cb_t)teco_state_ctlc_initial,
-	/*
-	 * At the end of a macro, "return" is allowed, but basically a no-op.
-	 */
-	.end_of_macro_cb = NULL,
-	/*
-	 * The state should behave like teco_state_start
-	 * when it comes to function key macro masking.
-	 */
-	.is_start = TRUE,
-	.keymacro_mask = TECO_KEYMACRO_MASK_START | TECO_KEYMACRO_MASK_CASEINSENSITIVE
+TECO_DEFINE_STATE_START(teco_state_ctlc,
+	.initial_cb = (teco_state_initial_cb_t)teco_state_ctlc_initial
 );
 
 static teco_state_t *