"header", "layout" and "paper" blocks as variables...

[padovani]

hi.
is there a way to put the header, layout and block values as variables?

I woul like to use something like

myheader = \header { ..... }
mylayout = \layout { .... }
mypaper = \paper { ....}

and then call these variables to construct my score...

I tried but I get errors like:

./instr/comhead.ly:69:8: error: syntax error, unexpected STRING
  
       tagline = ##f
./instr/comhead.ly:70:26: error: unknown escaped string: `\cm'
   left-margin = 1.5
                         \cm
./instr/comhead.ly:71:27: error: unknown escaped string: `\cm'
   right-margin = 1.5
                          \cm
./instr/comhead.ly:72:25: error: unknown escaped string: `\cm'
   top-margin = 0.5
                        \cm
./instr/comhead.ly:73:28: error: unknown escaped string: `\cm'
   bottom-margin = 0.5
                           \cm


(continues.....)

any tips? Or am I doing something stupid?
thanks