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pseudo-variable_20side_20effects

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pseudo-variable_20side_20effects [2018/03/31 13:19] – external edit 127.0.0.1pseudo-variable_20side_20effects [2024/01/05 00:21] (current) – external edit 127.0.0.1
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 //by Richard Russell, March 2011//\\ \\  One thing that distinguishes the [[http://www.bbcbasic.co.uk/bbcwin/manual/bbcwin2.html#pseudovars|pseudo-variables]] (**HIMEM**, **LOMEM**, **PAGE**, **PTR#** and **TIME**/**TIME$**) from regular variables is that writing or reading a pseudo-variable may have a //side effect// in addition to what you would expect it to do. So for example a statement like:\\  //by Richard Russell, March 2011//\\ \\  One thing that distinguishes the [[http://www.bbcbasic.co.uk/bbcwin/manual/bbcwin2.html#pseudovars|pseudo-variables]] (**HIMEM**, **LOMEM**, **PAGE**, **PTR#** and **TIME**/**TIME$**) from regular variables is that writing or reading a pseudo-variable may have a //side effect// in addition to what you would expect it to do. So for example a statement like:\\ 
 +<code bb4w>
         LOMEM = LOMEM         LOMEM = LOMEM
 +</code>
 which you might not expect to do anything, actually does have an effect which could be important.\\ \\  The main side effects from accessing the pseudo-variables are listed below:\\ \\  which you might not expect to do anything, actually does have an effect which could be important.\\ \\  The main side effects from accessing the pseudo-variables are listed below:\\ \\ 
  
pseudo-variable_20side_20effects.1522502375.txt.gz · Last modified: 2024/01/05 00:16 (external edit)