Make indentation handling less broken.

We're probably not all the way there just yet, but at least it's less
hilariously broken this way than it was.

src/Snake/Actions.nqp

@@ -29,31 +29,14 @@ method string($/) { make $<quote_EXPR>.ast; }
 #method infix:sym<==>($/) { ... }
 #method infix:sym<!=>($/) { ... }
 
-method INDENT($/) {
-    my $new := $<sports>.ast;
-    my $old := @*INDENT[0];
-    if $new > $old {
-        nqp::unshift_i(@*INDENT, $new);
-    }
-    else {
-        nqp::die("Bad indentation: new level $new seen, but old level is greater ($old)");
-    }
-}
+method INDENT($/) { nqp::unshift_i(@*INDENT, $<sports>.ast); }
 
 method DEDENT($/) {
     my $new := $<EOF> ?? 0 !! $<sports>.ast;
     nqp::shift_i(@*INDENT) while $new < @*INDENT[0];
     nqp::die("Bad dedent: saw $new but expected @*INDENT[0]") if $new != @*INDENT[0];
 }
 
-method check-indent($/) {
-    if $<sports> {
-        my $got      := $<sports>.ast;
-        my $expected := @*INDENT[0];
-        nqp::die("Incorrect indentation: saw $got when expecting $expected") if $got != $expected;
-    }
-}
-
 method sports($/) {
     my $indent := 0;
     $indent := $indent + nqp::chars(~$/[0]);

src/Snake/Grammar.nqp

@@ -115,17 +115,17 @@ token INDENT {
     # Gobble up leading whitespace, push new indent onto stack (or die if bad
     # indent).
     #<!> # TODO
-    ^^ <sports> <.MARKER: 'INDENT'> || <.panic: "Dedent not at beginning of line!">
+    ^^ <sports> <?{ $<sports>.ast > @*INDENT[0] }> <.MARKER: 'INDENT'> || <.panic: "Dedent not at beginning of line!">
 }
 
 token DEDENT {
     # Gobble up leading whitespace, pop until we're done (or die if bad
     # indent).
-    [^^ <sports> <.MARKER: 'INDENT'> | $<EOF>=<?> $] || <.panic: "Indent not at beginning of line!">
+    [^^ <sports> <?{ $<sports>.ast < @*INDENT[0] }> <.MARKER: 'INDENT'> | $<EOF>=<?> $] || <.panic: "Indent not at beginning of line!">
 }
 
 token check-indent {
-    <.MARKED: 'INDENT'> || ^^ <sports>
+    <.MARKED: 'INDENT'> || ^^ <sports> <?{ $<sports>.ast == @*INDENT[0] }>
 }
 
 # Spaces or tabs. A valid Python indent consists of any number of spaces, then