Var FirstRun
!define FirstRunLoop '!insertmacro FirstRunLoop'
!macro FirstRunLoop FirstRunString
    StrCpy ${FirstRunString} ''
    ${Do}
        ${If} ${FirstRunString} != FirstRun
            ${IfThen} $FirstRun = 1 ${|} StrCpy ${FirstRunString} FirstRun ${|}
        ${Else}
            StrCpy ${FirstRunString} ''
        ${EndIf}
!macroend

!define GetFirstRun '!insertmacro GetFirstRun'
!macro GetFirstRun FirstRunString
        ${If} ${FirstRunString} != FirstRun
            ${IfThen} $FirstRun = 1 ${|} StrCpy ${FirstRunString} FirstRun ${|}
        ${Else}
            StrCpy ${FirstRunString} ''
        ${EndIf}
!macroend

Section
    StrCpy $FirstRun 1 ; or = 0
; *** or this way
    StrCpy $8 ''
    ${Do}
        ${GetFirstRun} $8
        ; segment code
        ${ReadLauncherConfig} $0 FileWrite$R0$8 Type
        ; segment code
    ${LoopUntil} $8 == ''

; *** or this way
    ${FirstRunLoop} $8
        ; segment code
        ${ReadLauncherConfig} $0 FileWrite$R0$8 Type
        ; segment code
    ${LoopUntil} $8 == ''

SectionEnd