Syntax Explanation

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Each page contains both syntax notation and a diagram.

The non-diagrammed syntax conventions are as follows
  • Uppercase syntax words are required BR keywords that may be specified as acceptable abbreviations.
  • Although the keywords are uppercase in the diagrams, they may be specified in upper, lower or mixed case.
  • Items in [square brackets] are optional.
  • [,...] indicates the preceding term can be repeated (comma separated).
  • A bar | within a braced group (e.g. {aaa|bbb} )signifies OR, meaning the braces enclose a bar separated list. One of the bar separated terms must be specified.
  • 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.
  • Punctuation, other than "{}, [], <> and ...", must be specified - i.e. quotation marks, commas, colons etc.
  • Spaces between items mean one or more space is required.
  • Additional spaces may be specified ahead of or following commas.

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
      <number>|<numeric variable>|<numeric internal function>|<numeric user-defined function>|<conditional expression>
  
             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 which produces a numeric value>
  
             numeric user-defined function
             <A user defined function that returns a numeric value>
           conditional expression
           <number> <comparison operator> <number>
           |<numeric expression> <comparison operator> <numeric expression>
           |<numeric expression> <comparison operator> <numeric expression> {AND|OR} <conditional expression>
           |<string expression> <comparison operator> <string expression>
           |<string expression><comparison operator><string expression> {AND|OR} [NOT]<string expression><comparison operator><string expression>}
  
      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>