If a user has set Keypad mode to Links are numbered, or Form fields are numbered, or Links and form fields are numbered as the default or for the current session via the Options menu, then hypertext links (and form fields, depending on the keypad mode) are prefixed with numbers in square brackets. Entering a keyboard or keypad number is treated as an F_LINK_NUM command, and should invoke the Follow link (or goto link or page) number: statusline prompt for a potentially multiple digit number corresponding to an indicated link number. If RETURN is pressed to terminate the number entry (e.g., 123) and it corresponds to a hypertext link, Lynx will retrieve the document for that link as if you had paged or used other navigation commands to make it the current link and then ACTIVATE-ed it. The prompt can be invoked via '0', but it will not be treated as the lead digit for the number entry, whereas '1' through '9' both invoke the prompt and are treated as the first digit. In Form fields are numbered or Links and form fields are numbered mode, if the number corresponds to a form field you will be positioned on that field, but if it is a submit button it will not be ACTIVATE-ed.
If the number entered at the prompt has a 'g' suffix (e.g., 123g), then Lynx will make the link corresponding to that number the current link, paging as appropriate if the link does not appear in the currently displayed page. The 'g' suffix is inferred (need not be entered) for form fields in Form fields are numbered or Links and form fields are numbered mode.
Alternatively, if the number is given a 'p' suffix (e.g., 123p), Lynx will make the page corresponding to that number the currently displayed page, and the first link on that page, if any, the current link. The 'g' and 'p' suffixes thus convert the Follow link (or goto link or page) number: feature to an advanced navigation aid.
Finally, a user may add a + or - suffix to a number command to indicate jumping forward or back relative to the current link or page. For example, typing 1g+ followed by RETURN will move the current link to the next numbered link, skipping any intervening pages or unnumbered links; 1g- goes to the preceding numbered link. On a page without links, 3g+ goes to the 3rd link following the page. 5p+ skips ahead 5 pages, and so on. You can also enter 5+ or 5-, which will activate the 5th link ahead/behind where you are currently positioned. Note that typing 1g+ is different from typing a down arrow in that 1g+ skips pages containing no links, or intervening non-numbered links, such as form fields when form fields are not numbered. It also differs from the <tab> command in that 1g+ does not skip over whole textareas, unless form fields are not numbered.
NOTE: 1+g 1-g 1+p 1-p are all recognised as equivalent to 1g+ 1g- 1p+ 1p- . Any other (mistyped) characters end the formula: e.g. 1gh+ is treated as 1g.
If the user has set Keypad mode to Numbers act as arrows, then only '0', rather than every number, will be treated as an F_LINK_NUM command for invoking the Follow link (or goto link or page) number: prompt. The '0' will not be treated as the first digit for the number, or number plus suffix, entry.
Numbers are associated with form fields only when Form fields are numbered or Links and form fields are numbered mode has been selected. If you have selected Numbers act as arrows or Links are numbered mode, you can seek form fields in the document via WHEREIS searches for strings in their displayed values. If they are INPUT or TEXTAREA fields with no values as yet, you can use two or more underscores as the search string, because underscores are used as placeholders for form fields in the displayed document.
When you have invoked a popup window for a list of OPTIONs in a form's SELECT block, each OPTION is associated with a number, and that number will be displayed in Form fields are numbered or Links and form fields are numbered mode. In any keypad mode, the F_LINK_NUM ('0') command will invoke a Select option (or page) number: prompt, and you can enter a number, and optionally a 'g' or 'p' suffix, to select or seek an OPTION in that list. If only a number is entered at the prompt, the corresponding OPTION will be selected and the popup will be retracted. If the 'g' suffix is included, then you will be positioned on the corresponding OPTION in the list, paging through the list if necessary, but it will not be treated as selected unless you enter the ACTIVATE (RETURN or right-arrow) command when positioned on the OPTION. For purposes of paging (e.g., in conjunction with the 'p' suffix), a page is defined as the number of OPTIONs displayed within the vertical dimension of the popup window. Finally, the + and - suffixes can be used to move forward or back from the current option or page in a popup menu, similarly to the way they are used for links For example, while viewing a popup window, the user can type 3p+ and RETURN to skip ahead 3 pages, and 50g- will move the current selection back 50 options. This will work whether or not keypad mode is Form fields are numbered or Links and form fields are numbered since options are numbered internally. If form field numbering is turned off, the option numbers won't appear on screen, but the user can still navigate using these commands.
Note that HTML can be structured so that it includes hidden links, i.e., without a visible link name intended for ACTIVATE-ing the link. Such links may be created, for example, by making an IMG element the sole content of an Anchor element, and including an ALT="" attribute name/value pair to suppress access to the link when the browser does not have support for image handling available. They also can be created by having truly empty Anchor content, in cases for which the value of an Anchor's HREF attribute is intended as a navigation aid for robots (typically indexers) and not as content for a browser's rendition of the document. With the -ismap command line switch, Lynx will additionally treat a link to a server-side image maps as hidden if there also is a client-side map for the same image. Finally, in some cases links that are not intended to be hidden may effectively become hidden links because of bad HTML. The hidden links differ from Anchors that have only a NAME or ID attribute name/value pair (intended as positioning targets from other links which do have HREF attributes and values that include a fragment).
Lynx respects instructions for hidden links and normally does not include them in the rendition of the document. However, if the command line switch -hiddenlinks=merge is used, such links will still be numbered in sequence with other links which are not hidden, and if Links are numbered mode is also on, link numbers will appear for them in the displayed text (except for links to image maps which are hidden because of -ismap). If -hiddenlinks=listonly or -hiddenlinks=ignore is in effect, hidden links will not be shown in the text even in links are numbered mode. Not using a -hiddenlinks flag at all is equivalent to -hiddenlinks=listonly.
If a document includes hidden links, they will be reported, with appropriate labeling, in the menus created for the LIST ('l') or ADDRLIST ('A') commands, unless -hiddenlinks=ignore is used. They can then be ACTIVATE-ed via those menus. Also, if a link was hidden because of an ALT attribute in an IMG element, it will be converted to a visible link whenever the IMAGE_TOGGLE ('*') command is used to create links for SRC attribute values of IMG elements, because this indicates that the user does have some form of image handling enabled via a helper application, or wishes to download files for subsequent use with a graphic browser or other suitable software.
HTML forms also may have fields with a HIDDEN attribute, indicating that a name/value pair for the fields should be included in the content submitted for the form, but the value should not be displayed in the rendered form. Lynx respects this attribute as well, and neither displays the HIDDEN field, nor assigns it a number for the F_LINK_NUM ('0') command and Form fields are numbered or Links and form fields are numbered keypad mode handling, nor includes an entry for it in the menus created for the LIST ('l') or ADDRLIST ('A') commands. However, the HIDDEN name/value pairs are included in any displays of submitted form content in the Information about the current document that is invoked by the INFO ('=') command.