(hif-token-regexp, hif-tokenize): Use it.
(hif-mathify-binop): New macro.
(hif-plus, hif-minus, hif-notequal, hif-greater, hif-less)
(hif-greater-equal, hif-less-equal): Use it.
(hif-logior, hif-logand): New functions.
(hif-math): Accept | and & as well.
(hide-ifdef-shadow): New face.
(hide-ifdef-toggle-shadowing): New function to toggle between
shadowing and making code invisible.
(hide-ifdef-mode-submap): Add binding for
hide-ifdef-toggle-shadowing.
(hide-ifdef-mode-menu): Add entry for
hide-ifdef-toggle-shadowing.
(hide-ifdef-region-internal): Give new overlay hide-ifdef
property. Shadow text when hide-ifdef-shadow is non-nil.
(hif-show-ifdef-region): Remove overlays with hide-ifdef
property set.
(hif-hide-line): Use when instead of if.
(hide-ifdef-initially, hide-ifdef-read-only, hide-ifdef-lines):
Remove unneeded * from doc-strings.
(hide-ifdef-mode): Set line-move-ignore-invisible.
(hide-ifdef-region-internal): New function.
(hide-ifdef-region): Use it.
(hif-defined): Return an integer.
(hif-infix-to-prefix): Remove.
(hif-tokenize): Parse from the buffer rather than from a string.
Correctly tokenize integers. Use forward-comment.
(hif-expr): Use hif-or.
(hif-term): Use hif-and.
(hif-factor): Use hif-not. Handle numbers properly.
Don't require parenthesis around `defined's argument.
(hif-and, hif-or, hif-not): New funs.
(hif-canonicalize): Pass a region to hif-tokenize. Use hif-not.
(hif-hide-line): Don't hide the \n before the line.
(hif-possibly-hide): Correctly handle numeric evaluation results.
(hide-ifdef-mode-submap): Put the def in the defvar.
Use substitute-key-definition.
(hide-ifdef-mode): Use define-minor-mode.
(hif-outline-flag-region): Remove.
(hif-show-all): Define in terms of hif-show-ifdef-region.
(hif-after-revert-function): Rename from hif-before-revert-function.
(hide-ifdef-region, hif-show-ifdef-region): Use overlays.
(hif-tokenize): Use with-syntax-table.
(hif-make-range): Use `else' also for `else-p'.
(hif-range-else-p): Remove.
(hif-find-range): Simplify.
(hif-hide-line): Don't bother preserving buffer-modified-p.
(hide-ifdefs, show-ifdefs, hide-ifdef-block, show-ifdef-block):
Don't use selective-display and inhibit-read-only.
Move declaration before first use.
(hif-parse-if-exp, hif-nexttoken, hif-expr, hif-term, hif-eq-expr,
hif-math, hif-factor): Rename token to hif-token and token-list to
hif-token-list.
(hif-token, hif-token-list): Declare them.
(hif-find-ifdef-block): Return cons of top and bottom point
instead of setting dynamically bound variables.
(hide-ifdef-block, show-ifdef-block): Use return value of
hif-find-ifdef-block.
(hif-less-equal): New functions.
(hif-tokenize): Handle new tokens >, <, >=, <=.
(hif-eq-expr): Handle parsing these new tokens.
(hif-token-regexp): Match >, <. >=, <=
