From 89f393e3492381e2f1115a6c33cf576624305ffa Mon Sep 17 00:00:00 2001
From: Devine Lu Linvega <aliceffekt@gmail.com>
Date: Fri, 24 May 2024 18:56:06 -0700
Subject: [PATCH] Handle empty register writes at the register level

---
 src/modal.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/modal.c b/src/modal.c
index 0c1af6e..32ba312 100644
--- a/src/modal.c
+++ b/src/modal.c
@@ -123,16 +123,17 @@ file_import(char *path, char *ptr)
 	return copy("NAF", ptr, 3);
 }
 
-static int
+static void
 write_reg(char r, char *reg)
 {
-	char *origin = dst_;
 	switch(r) {
 	case ':': device_write(reg); break;
 	case '~': {
 		unsigned char c;
+		char *origin = dst_;
 		while(fread(&c, 1, 1, stdin) && c >= ' ') *dst_++ = c;
 		if(feof(stdin)) dst_ = copy("EOF", dst_, 3);
+		if(origin == dst_) dst_--;
 		break;
 	}
 	case '_': {
@@ -172,7 +173,6 @@ write_reg(char r, char *reg)
 	}
 	default: dst_ = copy(reg, dst_, walk(reg) - reg);
 	}
-	return dst_ - origin;
 }
 
 static int
@@ -193,7 +193,7 @@ static int
 apply_rule(Rule *r, char *s)
 {
 	unsigned char rid;
-	char c, *a = r->a, *b = r->b, *origin = dst_, *reg, last = 0;
+	char c, *a = r->a, *b = r->b, *origin = dst_, *reg;
 	/* phase: clean regs */
 	while(stack_ != stack) regs[(int)*(--stack_)] = 0;
 	/* phase: match rule */
@@ -215,16 +215,10 @@ apply_rule(Rule *r, char *s)
 	if(!spacer(c)) return 0;
 	/* phase: write rule */
 	while((c = *b++))
-		if(c == '?' && (rid = *b) && (reg = regs[rid])) {
-			b++;
-			if(!write_reg(rid, reg)) {
-				if(*b == ' ')
-					b++;
-				else if(last == ' ')
-					dst_--;
-			}
-		} else
-			*dst_++ = last = c;
+		if(c == '?' && (rid = *b) && (reg = regs[rid]))
+			write_reg(rid, reg), b++;
+		else
+			*dst_++ = c;
 	if(dst_ == origin) {
 		while(*s == ' ') s++;
 		if(*s == ')' && *(dst_ - 1) == ' ') dst_--;