[Newbie] différence between macro and functions

[mumuri]

I only want to know the différence between a macro and a function in NSIS.

What is the 'influence' on the finale exe file ?? Is this file bigger if i use a macro ??

[deguix]

Functions:

- Create smaller installers. The reason is that they are permanent codes called from one point in the script.

- They are difficult to use. You have to keep pushing and poping variables to get the parameters and create an output.

- They are only used at run time.

- They are used to create custom pages and modify other installer aspects.

Macros:

- Create bigger installers (except when using only for compile time instructions). The reason is that they are copied codes pasted where you want to "!insertmacro" them.

- They are easy to use. They are called in the form of "!insertmacro Command Parameters".

- They are used on both compile time and run time.

[mumuri]

ok thanks

[deguix]

Just a comment, a macro create a bigger installer when used more than once. If you would use a macro and a function with the same contents for 1 time, they would occupy the same size.

[mumuri]

i understand

Juste one more thing

IF the function is just use once, we d better use a macro ??

I mean ,to use a function you must 'call' it, so the 'éxécution time' will be longer than if we had use a macro, right ??

Or does the compiler understand that the function is just use once and then, insert the function code directly in the main code (without the 'call')

[deguix]

Yes, that's the only exception where the !macro wins about the size.

[Afrow UK]

If you want to use the same code more than once, you should use it within a Function, and call it with a macro.

Example:

code:
Function Blah

Exch $R0

Push $R1

...



Pop $R1

Exch $R0

FunctionEnd



!macro CallBlah INPUT

 Push "${INPUT}"

  Call Blah

!macroend

Then in sections or functions:

code:
!insertmacro CallBlah "input string / var"

Pop $R0 ;output



...

-Stu

[mumuri]

yes you "re right the code will be easyer to understand

thanks

but there is a little problem

if we have this case

call Function1
Pop $R1

Push $R1
call Function2

With the macro we can not do that (if we put the Push $R1 / call Function2 in the macro).

call Function1
call Function2

[iceman_k]

Doesn't MakeNSIS compress the instructions as well?
In that case repeated macros would get compressed as well.
So, the resulting installer may be a little bit bigger (in the order of bytes rather than kb) but it would be more than repaid by the increase in ease of development.

[Afrow UK]

Just use the code like that then.

-Stu

[Comm@nder21]

or even integrate function1 into function2