[Cook] implicit rules and variables

[Fredrick Paul Eisele]

The following example is in the user's guide...

%.c %.h: %.y
    set match-mode-cook
{
    yacc -d %.y;
    mv yy.tab.c  %.c;
    mv yy.tab.h  %h;
}

What I want to know is if this ...

why = '%.y';

%.c %.h: [why]
    set match-mode-cook
{
    yacc -d %.y;
    mv yy.tab.c  %.c;
    mv yy.tab.h  %h;
}

... is equivalent?
Thanks