编译原理词法分析器、语法分析器python实现

P~D S D~L id ; D~L id ; D L~int L~float S~id = E ; S~if ( C ) S S~if ( C ) S else S S~while ( C ) do S S~S S C~E > E C~E < E C~E == E E~E + T E~E – T E~T T~F T~T * F T~T / F F~( E ) F~id F~int10