Syntax Explanation: Difference between revisions

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             conditional expression
             conditional expression
             <number> <numeric operator> <number>
             <number> <numeric operator> <number>
             <numeric expression> <numeric operator> <numeric expression>
             |<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>}
             |<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>
             <value><comparison operator><value> {AND <value><comparison operator><value>} {OR <value><comparison operator><value>} {NOT <value><comparison operator><value>}  
             |<value><comparison operator><value> {AND <value><comparison operator><value>} {OR <value><comparison operator><value>} {NOT <value><comparison operator><value>}  
    
    
               number
               number

Revision as of 19:21, 18 April 2014

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.
  • 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.
  • Punctuation must be used, 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.
  • Commas ahead of closing braces must be specified only between repeating terms.
  • A bar | signifies OR, meaning the item preceding the bar can be replaced with the item following it. 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>