Command `!insertmacro MyMacro` is very verbose so very often script writer do this trick:
<code>
#define macro a b
!macro MyMacro
# ...
!macroend
#define shortcut for macro
!define MyMacro `!insertmacro MyMacro`
#use macro
${MyMacro} $a $b
</code>
It would be very handy if NSIS has syntax like `!{MyMacro}` for macros instead of `!insertmacro MyMacro`.