diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Grasp/IP.hs | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/src/Grasp/IP.hs b/src/Grasp/IP.hs index 6a4d452..294c92d 100644 --- a/src/Grasp/IP.hs +++ b/src/Grasp/IP.hs @@ -6,7 +6,8 @@ module Grasp.IP ( isEmpty, peek, push, - pop + pop, + shift ) where @@ -39,5 +40,8 @@ push :: GNode -> IP -> IP push n (IP p) = IP (n:p) pop :: IP -> IP -pop (IP p) = if (length p == 0) then IP p else IP (tail p) +pop (IP p) = if (length p == 0) then empty else IP (tail p) + +shift :: GNode -> IP -> IP +shift n (IP p) = if (length p == 0) then empty else IP (n:(tail p)) |