92 lines
1.5 KiB
Plaintext
92 lines
1.5 KiB
Plaintext
note
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description: "External iteration cursor for {DATABASE_HANDLER}"
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date: "$Date: 2014-08-20 15:21:15 -0300 (mi., 20 ago. 2014) $"
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revision: "$Revision: 95678 $"
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class
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DATABASE_ITERATION_CURSOR [G]
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inherit
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ITERATION_CURSOR [G]
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ITERABLE [G]
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create
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make
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feature -- Initialization
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make (a_handler: DATABASE_HANDLER; a_action: like action)
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-- Create an iterator and set `db_handlet' to `a_handler'
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-- `action' to `a_action'
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do
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db_handler := a_handler
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action := a_action
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ensure
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db_handler_set: db_handler = a_handler
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action_set: action = a_action
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end
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feature -- Access
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item: G
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-- Item at current cursor position.
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do
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Result := action.item ([db_item])
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end
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db_item: DB_TUPLE
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-- Current element.
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do
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if attached {DB_TUPLE} db_handler.item as l_item then
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Result := l_item
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else
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check False then
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end
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end
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end
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feature -- Status report
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after: BOOLEAN
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-- Are there no more items to iterate over?
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do
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Result := db_handler.after
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end
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feature -- Cursor movement
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start
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-- Set the cursor on first element.
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do
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db_handler.start
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end
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forth
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-- Move to next position.
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do
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db_handler.forth
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end
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feature -- Cursor
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new_cursor: DATABASE_ITERATION_CURSOR [G]
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-- <Precursor>
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do
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Result := twin
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Result.start
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end
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feature -- Action
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action: FUNCTION [ANY, detachable TUPLE, G]
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-- Agent to create a new item of type G.
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feature {NONE} -- Implementation
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db_handler: DATABASE_HANDLER
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-- Associated handler used for iteration.
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end
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