A examples/lib/length.xyw

@@ -0,0 +1,16 @@ 
+; .include "lib/macros.xyw"
+
+; returns the length of a string (max: 255)
+; a16 -[xxw]- a8
+.label length
+   POPxw ; store start address
+   $00 POPx ; counter
+   .label length.loop
+     ; if at end of string, go to end
+     LDBxw $00 EQU length.end JCNw
+     ; otherwise increment address and counter
+     INCxw
+     INCx
+     length.loop JMPw
+     .label length.end
+       PSHx RTS

A examples/lib/lengthw.xyw

@@ -0,0 +1,13 @@ 
+; returns the length of a string (max: 255)
+; a16 -[xwyw]- b16
+.label lengthw
+   POPxw ; store start address
+   $0000 POPyw ; counter
+   .label lengthw.loop
+     ; if at end of string, go to end
+     LDBxw $00 EQU lengthw.end JCNw
+     ; otherwise increment address and counter
+     INCxyw
+     lengthw.loop JMPw
+     .label lengthw.end
+       PSHyw RTS

A examples/lib/oneof.xyw

@@ -0,0 +1,18 @@ 
+; .include "lib/macros.xyw"
+
+; Checks if char a16 is one of chars in b16 (string)
+; a16 b16 -[xwyw]- a8
+.label oneof
+  POPyw
+  POPxw
+  .label oneof.loop
+    ; if at end of string, then no char is matching 
+    LDByw $00 EQU oneof.fail JCNw
+    ; if char matches, ok
+    LDBxyw EQU oneof.ok JCNw
+    INCyw oneof.loop JMPw
+    .label oneof.fail
+      $00 RTS
+    .label oneof.ok
+      $01 RTS
+

M xyw.vim → xyw.vim

@@ -11,7 +11,7 @@ " Comments
 syntax match xywComment ";.*$"
 
 " Directives
-syntax match xywDirective "\.\(include\|label\|macro\|string\|byte\)\>"
+syntax match xywDirective "\.\(include\|label\|macro\|string\|byte\|reserve\)\>"
 
 " Label definitions (name after .label)
 syntax match xywLabelDef "\(\.label\s\+\)\@<=[a-zA-Z_][a-zA-Z0-9_.\-]*"