DefDbl start_letter[-end_letter ][, ...]

start_letter
end_letter

DefDbl specifies that variables and arrays which aren't declared with a data type - or not declared at all - are implicitly declared of type Double if the first letter of their names matches a certain letter or lies within an inclusive range of letters.

This will make aNum a Double-precision decimal number since it is in the range of a-d:

'' Compile with -lang fblite or qb

#lang "fblite"

DefDbl a-d
Dim aNum 'implicit: As Double

Print Len(aNum) ' Prints 8, the number of bytes in a double.

• Only available in the -lang qb and -lang fblite dialects.
  
  

• None
  
  

• DefInt
  
• DefSng
  
• Dim
  
• Double