jonesforth depth

1 files changed, 3 insertions, 0 deletions

diff --git a/jefs.fs b/jefs.fs
index 8dd4a8e..b36d9e3 100644
--- a/jefs.fs
+++ b/jefs.fs
@@ -1,6 +1,7 @@
 \ i think something is going on with the stack. i dunno
 
 : cell+  8 + ;
+: cell-  8 - ;
 : say ( c-addr u -- )  swap 1 1 syscall3 drop ;
 : emit ( chr -- )  sp cell+ 1 swap 1 1 syscall3 2drop ;
 : cr  10 emit ;
@@ -266,6 +267,8 @@ make error-msgs #error-msgs cells allot
 : (words) ( lfa -- )  dup hidden? not if >nfa dup w@ swap 2 + swap say 2 spaces else drop then ;
 : words  latest @ begin ?dup 0<> while dup (words) @ repeat cr ;
 
+: depth ( -- n )  s0 @ sp @ - 16 - ;
+
 \ I/O {{{
 0 constant stdin
 1 constant stdout