Various constructions express a comparison between two arguments.
When the second argument (the point of reference) is adpositionally marked, ComparisonRef is used, regardless of its complement’s syntactic type:
Your face is as red as a rose/mine is. (ComparisonRef) 001
Your face is redder than a rose/mine is. (ComparisonRef) 002
See further examples at ComparisonRef.
In an as—as comparison, the scene role of the first argument (the object of the first as) is the role that would be operative if the construction were removed and only the first argument remained: e.g., I stayed as long as I could → I stayed long. The function of the first as is always Extent to reflect that it marks the degree on a scale:
Your face is as red as a rose. (Characteristic↝Extent) 004
I helped as carefully as I could. (Manner↝Extent) 005
I stayed as long as I could. (Duration↝Extent) 006
I helped as often as I could. (Frequency↝Extent) 007
I’ve eaten (twice) as much (food) as you. [amount of something] (Approximator↝Extent) 008
See #001 above.
Whole is used for the superset or gestalt licensed by a superlative:
See more at Whole.