font-slant-table

font-slant-table is a variable defined in `C source code'.
Its value is

[[0 reverse-oblique ro]
 [10 reverse-italic ri]
 [100 normal r unspecified]
 [200 italic i ot]
 [210 oblique o]]

Documentation:
Vector of font slant symbols vs the corresponding numeric values.
See `font-weight-table' for the format of the vector.