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本文探讨了IDL（Interface Definition Language）在接口文档中的应用，通过银行账户管理元素的例子，展示了如何使用IDL定义资源管理和操作，如存款和取款。文章强调了IDL在描述接口语法时的明确性，但指出了其在表达语义细节方面的不足。

idl编程，

https://www.omg.org/cgi-bin/doc?formal/02-06-39

CMU/SEI-2002-TN-015
27
8.2    IDL
A small sample interface specified in OMG’s IDL is shown in Figure 14. This interface is for 
an element that manages a bank account. The element provides resources to manage a finan-
cial account with attributes of “balance” and “owner.” The operations provided include 
“deposit” and “withdraw.” Although syntax is specified unambiguously in this type of docu-
mentation, semantic information is largely missing. For example, can a user make arbitrary 
withdrawals? Withdrawals only up to the current account balance? Up to a daily limit? Up to a 
minimum balance? If any of these restrictions is true, what happens if it’s violated? Is the max-
imum permissible amount withdrawn, or is the transaction as a whole canceled? 
IDL by itself is inadequate when it comes to fully documenting an interface, primarily because 
IDL offers no language constructs for discussing the semantics of an interface; without expres-
sion of the semantics, ambiguities and misunderstandings will abound.
interface Account { 
readonly attribute string owner; 
readonly attribute float balance; 
void deposit (in float amount); 
void withdraw (in float amount); 
};
interface CheckingAccount: Account { 
readonly attribute float overdraft_limit;
void order_new_checks (); 
};
interface SavingsAccount: Account {
float annual_interest (); 
};
interface Bank { 
CheckingAccount   open_checking   (in   string   name,   in   float
starting_balance); 
SavingsAccount   open_   savings   (in   string   name,   float
starting_balance);
};

https://resources.sei.cmu.edu/library/asset-view.cfm?assetid=5939