admin計算機英語：BASIC語言控制語句
BASIC Control Statements
Program control structures are primitive．Several forms of if statement man be available：
if
if
if
where
For arithmetic expressions a zero value can be treated as Boolean false，non-zero as true, Selection can also be performed by the on statement of the form：
On
If the expression evaluates to n, the nth statement number is selected for the destination of the GOTO.
Iteration may be provided by a for statement and sometimes also by a repeat statement, otherwise the GOTO is require.
Some versions of BASIC (including the standard) have subroutines (procedures and functions)with parameters．For others, control is simply passed to the start of a subroutine using GOSUB (instead of GOTO), and there is a [ENTER] statement to pass control back to the line below that of the GOSUB．
BASIC is unsuitable for large programs，lacking modularization features．It can be criticized for user even in small programs，as there are other languages available which require explicit declarations and encourage better detailed structuring, giving rise to better programming style and hence more readable programs. Standardization has come too late to pre-vent a proliferation of incompatible implementations, compromising portability of programs；this must beset against the advantage of the wide availability of BASIC 。
繙譯：
BASIC語言控制語句
程序控制結搆是原始的。if語句有幾種形式可用：
if<表達式>goto<語句號(碼)>
if<表達式>then<轉移>
if<表達式>then(轉移)else<轉移>
式中
對於算術表達式來說，一個零值可以作爲佈爾“假”來對待，而 非零值可作爲佈爾“真”來對待， 選擇也可由如形式on語句來實現：
on<表達式>goto<語句號（碼）表
如果該表達式的值被定爲m則 第n條語句號（碼）被選擇爲GOTO的目的地。
疊代可由for語句提供，有時也可由repeat語句提供，否則需要GOTO語句。
有些BASIC的版本（包括標準版本）具有帶蓡數的子程序（過程及函數）。對另一些版本來說，控制（轉移）是直接用GOSUB（代替GOTO）來 傳送給一個子程序的開始部的，還 有一個[ENTER]語句，用來將控制． （轉移）傳遞廻GOSUB之下的那一 行。
BASIC不適用於大型程序，區爲它缺少模塊化特性。即使對小應程序中的應用，BASIC也可能會受到批評，因爲還有另一些語言可用，這些語言要求顯示說明，更好的詳細結搆化編程，以養成良好的編程風格，從而編出更易讀色程序。標準化來得太晚，以致於天 能阻止不兼容的執行過程的激增．這樣就損害了程序的可移植性，這與BASIC的廣泛的適用性的優點是飛背道而馳的。這樣就損害了程序的可移植性，這 與BASIC的廣泛的適用性的優點是 飛背道而馳的。
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