Fixed a expression bug in postProcess
Fixed a expression bug in postProcess

aswathyjacob8/newtest,Yukaii/hackmd,Yukaii/hackmd,ironhack/hackmd,ironhack/hackmd,hackmdio/hackmd,Rory80Hz/hackmd,Rory80Hz/hackmd,jccrofty30/hackmd,ironhack/hackmd,jccrofty30/hackmd,PeterDaveHello/hackmd,jccrofty30/hackmd,xnum/hackmd,Rwing/hackmd,PeterDaveHello/hackmd,aswathyjacob8/newtest,Rory80Hz/hackmd,jackycute/HackMD,PeterDaveHello/hackmd,xnum/hackmd,jackycute/HackMD,Rwing/hackmd,Yukaii/hackmd,Rwing/hackmd,hackmdio/hackmd,jackycute/HackMD,janniklorenz/HackMD,janniklorenz/HackMD,janniklorenz/HackMD,aswathyjacob8/newtest,hackmdio/hackmd,xnum/hackmd