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+;;
+;; bank-account.scm
+;;
+;; Generic bank account records.
+;;
+;; ISC License
+;;
+;; Copyright 2023 Brmlab, z.s.
+;; Dominik Pantůček <dominik.pantucek@trustica.cz>
+;;
+;; Permission to use, copy, modify, and/or distribute this software
+;; for any purpose with or without fee is hereby granted, provided
+;; that the above copyright notice and this permission notice appear
+;; in all copies.
+;; 
+;; THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+;; WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+;; WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+;; AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+;; CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+;; OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+;; NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+;; CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+;;
+
+(declare (unit bank-account))
+
+(module
+ (
+  make-bank-account
+  bank-account-insert
+  )
+
+ (import scheme)
+
+ ;; Bank account is represented as a list with list with the following
+ ;; elements: list of transactions, account number, bank code. This
+ ;; allows cheap transaction prepending.
+ (define (make-bank-account number bank)
+   (list '() number bank))
+
+ ;; Prepends given transaction to given bank account. It expects the
+ ;; transactions list to be the first element of the bank account
+ ;; list.
+ (define (bank-account-insert account transaction)
+   (cons (cons transaction (car account))
+	 (cdr account)))
+
+ (define (make-bank-transaction id date amount currency varsym)
+   #f)
+
+ )