Unexpected Benefit of Inline Variables: Conditional Blocks
by Jim McKeeth
Inline variables is one of the cool new feature coming in 10.3. The obvious huge use case is loop control variables, but I just discovered another great use case while reviewing some code.
[delphi]procedure DoesSomething;
var
var1, var2: Integer;
begin
// use var1
{$IFDEF Something}
// use var1 & var2
{$ENDIF Something}
end;[/delphi]
This is a pattern I see a lot, and it generates a hint on var2 being unused based on the current compiler directive status.
[dcc32 Hint] myUnit.pas(123): H2164 Variable 'var2' is declared but never used in 'DoesSomething'
Now there are a number of ways to deal with this with more compiler directives, which is what I've done in the past, but I never like adding more compiler directives. It makes the code way more complicated and harder to maintain. Now with Inline Variables I can simplify it, make it easier to maintain, and hande the hint! (all of which makes me so happy!)
[delphi]procedure DoesSomething;
var
var1: Integer;
begin
// use var1
{$IFDEF Something}
var var2: Integer;
// use var1 and var2
{$ENDIF Something}
end;[/delphi]
What are some interesting ways you see inline variables benefiting you?
tags: 10.3 Rio - clean code - delphi - language features - News - Source Code