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--- outputting_20text_20with_20word-wrap [2018/03/31 13:19] – external edit 127.0.0.1
+++ outputting_20text_20with_20word-wrap [2024/01/05 00:22] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 =====Outputting text with word-wrap=====
-//by Richard Russell, August 2009//\\ \\  BBC BASIC (by default) automatically 'wraps' text that is output to the screen or the printer. If a character will not fit on the current line (or within the current text viewport) a 'new line' is generated and the character is displayed or printed at the beginning of the next line. The text viewport scrolls, or a new page is ejected from the printer, if necessary.\\ \\  Although this ensures that all text output is visible, it does often result in a word being split between two lines. It would usually be more desirable to perform a **word wrap**, that is if a character will not fit the entire word containing that character is moved to the next line. This is the kind of behaviour that a word processor usually has.\\ \\  The routines listed below implement word-wrap for text output to the screen or the printer. There are four procedures: **PROCww** outputs a string to the screen, **PROCvww** outputs a single character to the screen, **PROCwwp** outputs a string to the printer and **PROCvwwp** outputs a single character to the printer:\\ \\
+//by Richard Russell, August 2009//\\ \\  BBC BASIC (by default) automatically 'wraps' text that is output to the screen or the printer. If a character will not fit on the current line (or within the current text viewport) a 'new line' is generated and the character is displayed or printed at the beginning of the next line. The text viewport scrolls, or a new page is ejected from the printer, if necessary.\\ \\  Although this ensures that all text output is visible, it does often result in a word being split between two lines. It would usually be more desirable to perform a **word wrap**, that is if a character will not fit the entire word containing that character is moved to the next line. This is the kind of behaviour that a word processor usually has.\\ \\  The routines listed below implement word-wrap for text output to the screen or the printer. There are four procedures: **PROCww** outputs a string to the screen, **PROCvww** outputs a single character to the screen, **PROCwwp** outputs a string to the printer and **PROCvwwp** outputs a single character to the printer:
+<code bb4w>
        PROCww(A$)   : REM Equivalent to PRINT A$;
        PROCvww(C%)  : REM Equivalent to VDU C%
        PROCwwp(A$)  : REM Equivalent to OSCLI "OUTPUT 15" : PRINT A$; : OSCLI "OUTPUT 0"
        PROCvwwp(C%) : REM Equivalent to VDU 2,1,C%,3
-Note that **PROCww** and **PROCwwp** do not output a newline after the string; to do that you must concatenate **CHR$13+CHR$10** to the end of the string (or output them separately using **PROCvww** or **PROCvwwp**).\\ \\  Here are the routines necessary to implement word-wrap:\\ \\
+</code>
+Note that **PROCww** and **PROCwwp** do not output a newline after the string; to do that you must concatenate **CHR$13+CHR$10** to the end of the string (or output them separately using **PROCvww** or **PROCvwwp**).\\ \\  Here are the routines necessary to implement word-wrap:
+<code bb4w>
         DEF PROCww(A$)
         LOCAL I%
@@ Line 60: / Line 66: @@
         ENDIF
         ENDPROC
-Note that the usual restrictions caused by the use of **PRIVATE** apply. You must not attempt to resume execution if an error occurs (even an ESCape error) within the **PROCvww** or **PROCvwwp** routines. Ensure that any **ON ERROR** handler in your program aborts execution in such a case.
+</code>
+Note that the usual restrictions caused by the use of **PRIVATE** apply. You must not attempt to resume execution if an error occurs (even an ESCape error) within the **PROCvww** or **PROCvwwp** routines, unless you execute a **RESTORE LOCAL** as part of your error handler. Ensure that any **ON ERROR** handler in your program aborts execution in such a case.