HPR Character Position Forward

Move the cursor Pn columns to the right, on the line it is on. A 0 is taken as 1. The VT510 manual says that an attempt to move past the last position on the line stops at the last position.

It is a relative move, so origin mode makes no difference to it: the cursor moves Pn columns from wherever it is.

ECMA-48 names it for the data component, which a terminal does not have apart from its screen (§6, p. 14). Its counterpart going left is HPB, and the absolute form is HPA. The VT510 manual’s one-line summary of HPR is a copying error, as it is for HPA; the description beneath it is the right one.

Validation

HPR-1: One column by default

AB
\e[a
X

|AB_X_|

HPR-2: n columns

\e[2;1H
\e[3a
X

|_____|
|___X_|

HPR-3: Stops at the last column

\e[2;2H
\e[99a
X

|_____|
|____X|

HPR-4: The same in origin mode

\e[2;4r   # region is lines 2 to 4
\e[?69h   # allow left and right margins
\e[2;7s   # margins at columns 2 and 7
\e[?6h    # origin mode
\e[2;2H   # line 3, column 3 of the screen
X
\e[2a
Y
\e[?6l

|________|
|________|
|__X__Y__|
|________|

The Y should be two columns past the cell after X, on the same line, which is what esctest2’s test_HPR_IgnoresOriginMode checks. libghostty-vt moves it down as well. HPR there is setCursorPos(current line + 1, current column + 1 + Pn), and in origin mode setCursorPos adds the margins to both, so the line the cursor is on is offset by the top margin and the column by the left margin.