Syntax Explanation: Difference between revisions

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All program lines require a line number.
All program lines require a line number.


===Example 1: Delete Statement===
===Example: Delete Statement===


  DELETE #<file number>[,REC=<numeric expression>|,KEY=<string expression>][,RESERVE|,RELEASE] : {<error condition> <line ref>[,]}
  DELETE #<file number>[,REC=<numeric expression>|,KEY=<string expression>][,RESERVE|,RELEASE] : {<error condition> <line ref>[,]}

Revision as of 18:45, 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.

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>