A examples/lib/trimstart.xyw

@@ -0,0 +1,22 @@ 
+; UNTESTED
+; .include "lib/oneof.xyw"
+
+; Pushes the address of string trimmed at start
+; a16 -> b16
+.label trimstart
+  ; Save string address
+  POPxw ; start address (to return) m
+  .label trimstart.loop
+    ; if space, trim
+    PSHxw trimstart.spaces oneof JSRw 
+    trimstart.remove JCNw
+    ; otherwise return (at start of string)
+    trimstart.end JMPw
+    .label trimstart.remove
+      ; remove and increment start
+      $00 STBxw INCxw trimstart.loop JMPw
+    .label trimstart.end
+      PSHxw RTS
+      
+.label trimstart.spaces
+  .byte $20 $09 $0A $0D $00