Tech Tip: Adding type suffix to variables as a memory aid

PRODUCT: 4D | VERSION: 13.2 | PLATFORM: Mac & Win

Published On: April 19, 2013

When working with a large method with lots of variables of many types it can become difficult to remember what type a variable is. A helpful coding practice is to add a variable type prefix of suffix to all variables. The next time the a variable of a certain type is needed it is then easy to verify a variable of the correct type is being used.

Below are two examples of how to declare variables suffixed and prefixed with their types. Each developer will prefer their own style but regardless of prefix or suffix the aid of knowing the variable type is the same.

Local variables Suffixed with type

C_BOOLEAN($MyVar_B)
C_BLOB($MyVar_X)
C_DATE($MyVar_D)
C_GRAPH($MyVar_C) // C for Chart
C_INTEGER($MyVar_I)
C_LONGINT($MyVar_L)
C_PICTURE($MyVar_G) // G for Graphic
C_POINTER($MyVar_P)
C_REAL($MyVar_R)
C_STRING(255;$MyVar_Snnn) // nnn replaced with string size
C_TEXT($MyVar_T)
C_TIME($MyVar_H) // H for hour

Local variables Prefixed with type

C_BOOLEAN($B_MyVar)
C_BLOB($X_MyVar)
C_DATE($D_MyVar)
C_GRAPH($C_MyVar) // C for Chart
C_INTEGER($I_MyVar)
C_LONGINT($L_MyVar)
C_PICTURE($G_MyVar) // G for Graphic
C_POINTER($P_MyVar)
C_REAL($R_MyVar)
C_STRING(255;$Snnn_MyVar) // nnn replaced with string size
C_TEXT($T_MyVar)
C_TIME($H_MyVar) // H for hour

Commented by Justin Leavens on April 26, 2013 at 12:43 PM

But only one method is correct :-)