Differences between Decimal BASIC and True BASIC

2. Syntax

True BASIC allows the formats on the left-hand side, while Decimal BASIC allows only the formats on the right-hand side.

      ELSE IF            →  ELSEIF
      GET POINT x, y     →  GET POINT: x, y
      A$[1:3]            →  A$(1:3)
      WHEN ERROR IN      →  WHEN EXCEPTION IN
      CAUSE ERROR        →  CAUSE EXCEPTION
      CALL sub(A())      →  CALL sub(A)
      DEF ～ END DEF     →  FUNCTION ～ END FUNCTION
      DECLARE DEF        →  DECLARE FUNCTION
      RESET #n:          →  SET #n: POINTER
      ORG STREAM         →  ORGANIZATION STREAM, RECTYPE INTERNAL

Substring modifiers can be applied only to string variables, string expressions except string variables cannot have substring modifiers.
Use a originally enhanced built-in function SUBSTR$(a$,m,n) to get a substring of a string expression.