Display the exponent from a binary floating point number as a decimal value
Haskell, 33 bytes

foldl1(\x y-&gt;x*2+y-1).take 8.tail

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Input is a list of integers 0 or 1.
It's slightly shorter to foldl1 by x*2+y-1 than to subtract 127 at the end. This works because
  foldl1 (\x y-&gt;x*2+y-1) [a,b,c,d,e,f,g,h]
= ((((((a*2+b-1)*2+c-1)*2+d-1)*2+e-1)*2+f-1)*2+g-1)*2+h-1
= a*128 + b*64-64 + c*32-32 + d*16-16 + e*8-8 + f*4-4 + g*2-2 + h-1
= 128a + 64b + 32c + 16d + 8e + 4f + 2g + h - 127
= fromBinary[a,b,c,d,e,f,g,h]-127