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[Fredrik Andersson]

I wonder if it is possible to hide part of text in Emacs?
I would like to compress/expand the text inside a subroutine. 

Before  compression:
--------------------
Function name(a,var z:boolean):Boolean;
Var
 x:Real;
 z:Bollean;
BEGIN
 x:=4;
 z:=True;
END;

After compression:
------------------
Function name(a,var z:boolean):Boolean;


Thanks in advance
Fredrik Andersson