Syntax Explanation: Difference between revisions

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               <One with a numeric value>
               <One with a numeric value>


    string expression
      string expression
    <string internal function>|<string user-defined function>|<string constant>|<string variable> {<substring operations>} {<concatenation operations>}
      <string internal function>|<string user-defined function>|<string constant>|<string variable> {<substring operations>} {<concatenation operations>}
    
    
            string internal function
              string internal function
          <An [[:Category:Internal Functions|internal function]] with a string value>
              <An [[:Category:Internal Functions|internal function]] with a string value>
    
    
            string user-defined function
              string user-defined function
          <One with a string value>  
              <One with a string value>  
    
    
            string constant
              string constant
            <"a series of characters enclosed in quotation marks">  
              <"a series of characters enclosed in quotation marks">  
    
    
            string variable
              string variable
            <1-30 alphanumeric characters and underscores, the first of which must be a letter (but not [[FN]]) which ends in a $. They also cannot be [[reserved words]]>
              <1-30 alphanumeric characters and underscores, the first of which must be a letter (but not [[FN]]) which ends in a $. They also cannot be [[reserved words]]>





Revision as of 18:47, 17 April 2014

Each page contains both syntax notation and a diagram.

The non-diagrammed syntax conventions are as follows
  • Uppercase words are BR keywords that must be used exactly or with acceptable abbreviations.
  • Items in [square brackets] are optional.
  • Items in {braces} can be repeated 0 or more times.
  • Terms in <angle brackets> must be replaced with appropriate items. When not inherently logical i.e. <#file number>, item descriptions are found in subsequent lines.
  • Special characters must be used, i.e. quotation marks, commas, colons etc.
  • Spaces between items mean one space or more is required.
  • A bar | signifies OR, meaning the item preceding the bar can be replaced with the item following it, or the item following a bar following that one. For example:
blue black|grey|white red pink|orange

Satisfactory outcomes would be:

blue black red pink     
blue grey red orange  
blue white red pink 
etc...
  • All program lines require a line number (although it's not included in syntax notation).

Example: Delete Statement

DELETE #<file number>[,REC=<numeric expression>|,KEY=<string expression>][,RESERVE|,RELEASE] : {<error condition> <line ref>[,]}
      numeric expression
      <conditional expression>|<number>|<numeric variable>|<numeric internal function>|<numeric user-defined function>
  
           conditional expression
           <number> <numeric operator> <number>
           <numeric expression> <numeric operator> <numeric expression>
           <numeric expression> <numeric operator> <numeric expression>{AND <numeric expression> <numeric operator> <numeric expression} {OR <numeric expression> <numeric operator> <numeric expression>}
           <value> <comparison operator> <value>
           <value><comparison operator><value> {AND <value><comparison operator><value>} {OR <value><comparison operator><value>} {NOT <value><comparison operator><value>} 
  
             number
             <A rational number up to 15 digits long>. See RD in BRConfig.sys.
  
             numeric variable
             <1-30 alphanumeric characters and underscores, the first of which must be a letter (but not FN). They also cannot be reserved words> 
  
             numeric internal function
             <An internal function with a numeric value>
  
             numeric user-defined function
             <One with a numeric value>
      string expression
      <string internal function>|<string user-defined function>|<string constant>|<string variable> {<substring operations>} {<concatenation operations>}
  
             string internal function
             <An internal function with a string value>
  
             string user-defined function
             <One with a string value> 
  
             string constant
             <"a series of characters enclosed in quotation marks"> 
  
             string variable
             <1-30 alphanumeric characters and underscores, the first of which must be a letter (but not FN) which ends in a $. They also cannot be reserved words>