[Xy-pic] injection

[Vadim Yu. Radionov]

Dear Oliver!

On Thu, 9 Oct 2003, Les Saper wrote:

> Dear Olivier,
>
> I define a tip style in the preamble:
>
> \newdir^{ (}{{}*!/-5pt/@^{(}}%  % A new tip style for right hook arrows.
>                                 % This means the object given by
>                                 % directional ^{(} has its reference point
>                                 % shifted ! by the vector /-5pt/ .
>
> Then to produce a righthook arrow in an xymatrix I use (for
> example):
>
> \ar@{^{ (}->}[r]
>
> Hope this helps.
>
> - Les

This is an excellent XYpic code; but it looks quite different from
\hookrightarrow.  For horizontal arrows, you can type

\xymatrix{A \lhook\mkern-7mu \ar[r] & B}

together with

\entrymodifiers={+!!<0pt,\fontdimen22\textfont2>}

and similar for \hookleftarrow

Sincerely yours,
Vadim