Description: Define class of all Hilbert spaces. Based on Proposition 4.5, p. 176, Gudrun Kalmbach, Quantum Measures and Spaces, Kluwer, Dordrecht, 1998. (Contributed by NM, 7-Oct-2011) (Revised by Mario Carneiro, 16-Oct-2015)
|- Hil = { h e. PreHil | dom ( proj ` h ) = ( ClSubSp ` h ) }
|- Hil
|- h
|- PreHil
|- proj
|- ( proj ` h )
|- dom ( proj ` h )
|- ClSubSp
|- ( ClSubSp ` h )
|- dom ( proj ` h ) = ( ClSubSp ` h )
|- { h e. PreHil | dom ( proj ` h ) = ( ClSubSp ` h ) }