Eiffel Introduction
Eiffel introduction
Rensselaer, 2000
James C. McKim, JR, Rensselaer At Hartford
K] [N g of @ r k translation
4.4 Test_Stack
Class test_stack
CREATION MAKE_TEST
Feature {none}
Si: my_stack [integer]; ss: my_stack [string]
Make_test Is
DO
TEST_INTEGER_STACK
Test_string_stack
end
TEST_INTEGER_STACK IS
DO
!! si.make (3)
Si.push (3)
Si.push (2)
Si.push (1)
IO.PUTINT (Si.Depth) o.new_line
IO.PUTINT (Si.Top) o.new_line
Si.POP
IO.PUTINT (Si.Top) o.new_line
Si.POP
IO.PUTINT (Si.Top) o.new_line
Si.POP
end
Test_String_Stack IS
DO
!! ss.make (10)
SS.PUSH ("in dixie.")
SS.PUSH ("I Was")
ss.push ("oh, i wish")
IO.PUTSTRING (SS.TOP)
SS.POP
IO.PUTSTRING (SS.TOP)
SS.POP
IO.PUTSTRING (SS.TOP) o.new_line
end
end
4.5 Stack Class (another implementation)
Class my_stack [g]
Creation make
Feature {any}
Capacity: integer
DEPTH: INTEGER IS
DO
Result: = Current_Depth
end
Push (x: g) IS
- make x The top item.
Require
NOT_FULL: Depth DO Current_Depth: = current_depth 1 S.PUT (x, current_depth) Top: = X Ensure Depth = Old Depth 1; TOP = X End - push Top: g - The item That Has Been on The Stack for the Least - Amount of Time. - Require - not_empty: depth> 0 POP IS - Remove the top item. Require NOT_EMPTY: DEPTH> 0 DO Current_Depth: = current_depth - 1 IF current_Depth> 0 THEN Top: = S.Item (current_depth) end Ensure Depth = Old Depth - 1 - Top = The item Remaining on the stack (if any) - That Has Been there The Least Amount of Time. END - POP Feature {none} S: array [g] Current_Depth: Integer Make (C: Integer) - Initialize An Empty Stack with Capacity C.Require C> 0 DO Capacity: = C !! s.make (1, Capacity) Current_Depth: = 0 Ensure Capacity = C DEPTH = 0 END - MAKE end
