[PATCH 3/4] Allow multi-arm conditionals

["S. Gilles" <sgilles@xxxxxxxxxxxx>]

In addition to nested %?...%;, terminfo formats also allow multi-arm
conditionals, in the style of if..elif..elif..else..;; Handle those.
---
 test/tifmt.myr | 15 +++++++++++++++
 tifmt.myr      | 40 ++++++++++++++++++++++++----------------
 2 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/test/tifmt.myr b/test/tifmt.myr
index 0fd1dcf..026e4ad 100644
--- a/test/tifmt.myr
+++ b/test/tifmt.myr
@@ -83,6 +83,21 @@ const main = {
 				"%?%p1%t%?%p2%ttruetrue%etruefalse%;%efalsefalse%;", \
 				params, "truefalse") 
 		}],
+		[.name="cond-multi-arm-1", .fn={ctx
+			checkfmt(ctx, \
+				"%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m", \
+				[`termdraw.Int 5][:], "35m")
+		}],
+		[.name="cond-multi-arm-2", .fn={ctx
+			checkfmt(ctx, \
+				"%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m", \
+				[`termdraw.Int 13][:], "95m")
+		}],
+		[.name="cond-multi-arm-3", .fn={ctx
+			checkfmt(ctx, \
+				"%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m", \
+				[`termdraw.Int 221][:], "38;5;221m")
+		}],
 		/* oddballs */
 	][:])
 }
diff --git a/tifmt.myr b/tifmt.myr
index 4ae92b8..c16b2e3 100644
--- a/tifmt.myr
+++ b/tifmt.myr
@@ -84,14 +84,14 @@ const eval = {f, sb, str
 }
 
 const evalcond ={f, sb, str, pi
-	var cond, iftrue, iffalse
-	var start, depth, i
+	var condition
+	var start, depth, i, done, seen_e
 
-	cond = ""
-	iftrue = ""
-	iffalse = ""
+	condition = ""
 	start = pi#
 	depth = 1
+	done = false
+	seen_e = false
 	for i = pi#; i < str.len - 1; i++
 		if str[i] != ('%' : byte)
 			continue
@@ -100,24 +100,32 @@ const evalcond ={f, sb, str, pi
 			depth++
 		elif str[i + 1] == (';' : byte)
 			depth--
-		elif depth == 1 && str[i + 1] == ('t' : byte)
-			cond = str[start:i]
+		elif !done && depth == 1 && str[i + 1] == ('t' : byte)
+			condition = str[start:i]
 			start = i + 2
-		elif depth == 1 && str[i+ 1] == ('e' : byte)
-			iftrue = str[start:i]
+		elif !done && depth == 1 && str[i + 1] == ('e' : byte)
+			seen_e = true
+
+			eval(f, sb, condition)
+			if popi(f) != 0
+				eval(f, sb, str[start:i])
+				done = true
+			;;
+
 			start = i + 2
 		;;
 		if depth == 0
-			iffalse = str[start:i]
+			if !done && seen_e
+				eval(f, sb, str[start:i])
+			elif !done
+				eval(f, sb, condition)
+				if popi(f) != 0
+					eval(f, sb, str[start:i])
+				;;
+			;;
 			break
 		;;
 	;;
-	eval(f, sb, cond)
-	if popi(f) != 0
-		eval(f, sb, iftrue)
-	else
-		eval(f, sb, iffalse)
-	;;
 	pi# = i + 2
 }
 
-- 
2.14.3