You're pretty much out of luck.  With the mgrep utility you can get a complete list of all the _Env variables used in the library.

mgrep -c _Env maple.mla | grep -o '_Env[a-zA-Z0-9_]*' | sort -u > _Env

There are more than 600, most are not intended for the user.

Or use " ".

Or use " ".

I do not believe there is any packages that does this.

I had forgotten about ?StringTools[SearchAll]. You could use it in the following manner

charpos2 := proc(S :: string)
local char, p, pos;
uses ST = StringTools;
    pos := table();
    for char from "a" to "z" do
        # compute positions of char and uppercase char
        p := map2(op,1,[ST:-SearchAll([char,ST:-UpperCase(char)], S)]);
        if p <> [] then
            pos[char] := p;
        end if;
    end do;
    eval(pos);
end proc:

I had forgotten about ?StringTools[SearchAll]. You could use it in the following manner

charpos2 := proc(S :: string)
local char, p, pos;
uses ST = StringTools;
    pos := table();
    for char from "a" to "z" do
        # compute positions of char and uppercase char
        p := map2(op,1,[ST:-SearchAll([char,ST:-UpperCase(char)], S)]);
        if p <> [] then
            pos[char] := p;
        end if;
    end do;
    eval(pos);
end proc:

Here's my original suggestion, slightly modified and converted to a procedure.  It is intended to emulate the special evaluation rules of ?add, but provide multiple indexing. 

madd := proc(expr :: uneval, eq :: uneval)
local vars, rngs, i, n;
    vars := [lhs(eq)];
    rngs := eval([rhs(eq)]);
    n := nops(vars);
    if n <> nops(rngs) then
        error "variables, `%1', do not match ranges, `%2'", vars, rngs;
    end if;
    eval(subs('Add'=add, foldl('Add', 'expr', seq(vars[i]=rngs[i], i=1..n))));
end proc:
V := Array(1..4, i->i):
k := 23:  # this doesn't prevent the addition from working
madd(V[k]*j, (j,k) = ((1..4)$2));
                                                    100

Here's my original suggestion, slightly modified and converted to a procedure.  It is intended to emulate the special evaluation rules of ?add, but provide multiple indexing. 

madd := proc(expr :: uneval, eq :: uneval)
local vars, rngs, i, n;
    vars := [lhs(eq)];
    rngs := eval([rhs(eq)]);
    n := nops(vars);
    if n <> nops(rngs) then
        error "variables, `%1', do not match ranges, `%2'", vars, rngs;
    end if;
    eval(subs('Add'=add, foldl('Add', 'expr', seq(vars[i]=rngs[i], i=1..n))));
end proc:
V := Array(1..4, i->i):
k := 23:  # this doesn't prevent the addition from working
madd(V[k]*j, (j,k) = ((1..4)$2));
                                                    100

Generally, I like the separation.  However, there are cases---probaby dependent on my frustration level---where a brief example would clarify a convoluted description.  As you suggest, hyperlinks from the bullets to the examples (and from the Calling Sequence to the bullets) would be nice.  I don't believe that was doable with Maple's original help page viewer (the Classic interface), but may be with Standard. 

Generally, I like the separation.  However, there are cases---probaby dependent on my frustration level---where a brief example would clarify a convoluted description.  As you suggest, hyperlinks from the bullets to the examples (and from the Calling Sequence to the bullets) would be nice.  I don't believe that was doable with Maple's original help page viewer (the Classic interface), but may be with Standard. 

I agree with your thoughts on help pages---I've never liked the separate details page.  Maple's help pages can be created with sections collapsed, though that won't work with the command-line version (which is how I generally view help pages, albeit enhanced by Emacs; I could add a collapse feature to the Emacs maple help page viewer).

One aspect that I don't have a good solution for is the current separation of description and examples.  While I don't expect it to change, the separation of the description from the examples makes it harder to quickly comprehend a concept. I suspect that intermixing the two, if done carefully, could improve the quality of the documentation.  That is, a brief example could be given of a particular concept where it is introduced (in the description section).  As it is, I generally look first at the Calling Sequence, then search the Description section for the relevant parameter/form, then, if questions remain, look to the Examples section for the actual usage. 

I agree with your thoughts on help pages---I've never liked the separate details page.  Maple's help pages can be created with sections collapsed, though that won't work with the command-line version (which is how I generally view help pages, albeit enhanced by Emacs; I could add a collapse feature to the Emacs maple help page viewer).

One aspect that I don't have a good solution for is the current separation of description and examples.  While I don't expect it to change, the separation of the description from the examples makes it harder to quickly comprehend a concept. I suspect that intermixing the two, if done carefully, could improve the quality of the documentation.  That is, a brief example could be given of a particular concept where it is introduced (in the description section).  As it is, I generally look first at the Calling Sequence, then search the Description section for the relevant parameter/form, then, if questions remain, look to the Examples section for the actual usage. 

You could use the ?CurveFitting package to fit a smooth curve to the points.

You could use the ?CurveFitting package to fit a smooth curve to the points.

Thanks.  I suspected as much, but that form doesn't appear on the main ?plot page.

It seems a trifle strange that a Matrix works but not a two-dimensional Array (it plots, but not what is expected).  An Array is a more natural structure to hold data---Matrices seem better suited for LinearAlgebra operations.