(\y.y) w [w->2]
y [y->w, w->2]
-In the first step, we bind `w` to the term `2`, by saving this association in our environment. In the second step, we bind `y` to the term `w`. In the third step, we would like to replace `y` with whatever its current value is according to our scorecard/environment. But a naive handling of this would replace `y` with `w`; and that's not the right result, because `w` should itself be mapped onto `2`. On the other hand, in:
+In the first step, we bind `w` to the term `2`, by saving this association in our environment. In the second step, we bind `y` to the term `w`. In the third step, we would like to replace `y` with whatever its current value is according to our scorecard/environment. But a naive handling of this would replace `y` with `w`; and that's not the right result, because `w` should itself be mapped to `2`. On the other hand, in:
term environment
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