From b259cb68aa3f76d1e23b47be67d3fbeb6f6b62df Mon Sep 17 00:00:00 2001
From: Robin Haberkorn <robin.haberkorn@googlemail.com>
Date: Thu, 11 Feb 2016 13:09:39 +0100
Subject: optimized command execution in batch mode, during macro calls, loops
 etc.

 * SciTECO commands are implemented with immediate execution in mind.
   Those commands that do need to execute immediately while a string
   command is entered, can do so using StateExpectString::process().
   For simplicity, the parser just assumed that every input character
   should result in immediate execution (if the command supports it
   of course).
 * This lead to unnecessarily slow execution of commands like <I> or
   <S> in batch mode. E.g. a search was always repeated for every
   character of the pattern - a N character pattern could result in
   N searches instead of one.
   Also in interactive mode when executing a macro
   or repeating commands in a loop, immediate processing of string arguments
   is unnecessary and results in superfluous undo tokens.
 * These cases are all optimized now by being informed about
   the necessity of providing immediate feedback via State::refresh().
   This is used by StateExpectString to defer calling process() as
   long as possible.
 * For states extending StateExpectString, there is no change since
   they can already process arbitrarily long strings.
   The optimization is hidden in StateExpectString.
 * some allocations are now also avoided in StateExpectString::custom().
---
 src/parser.h | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

(limited to 'src/parser.h')

diff --git a/src/parser.h b/src/parser.h
index 1cd51c7..a1bfd75 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -54,9 +54,20 @@ public:
 	static void input(gchar chr);
 	State *get_next_state(gchar chr);
 
+	/**
+	 * Provide interactive feedback.
+	 *
+	 * This gets called whenever a state with
+	 * immediate interactive feedback should provide that
+	 * feedback; allowing them to optimize batch mode,
+	 * macro and many other cases.
+	 */
+	virtual void refresh(void) {}
+
 protected:
 	static bool eval_colon(void);
 
+	/** Get next state given an input character */
 	virtual State *
 	custom(gchar chr)
 	{
@@ -136,6 +147,7 @@ public:
  */
 class StateExpectString : public State {
 	StringBuildingMachine machine;
+	gsize insert_len;
 
 	gint nesting;
 
@@ -144,11 +156,12 @@ class StateExpectString : public State {
 
 public:
 	StateExpectString(bool _building = true, bool _last = true)
-			 : State(), nesting(1),
+			 : insert_len(0), nesting(1),
 			   string_building(_building), last(_last) {}
 
 private:
 	State *custom(gchar chr);
+	void refresh(void);
 
 protected:
 	virtual void initial(void) {}
-- 
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