Editing the way vi does

/config chooses between the ordinary box and vi's editing keys. The choice is written to ~/.bravebot, so it outlives the session and applies in every directory, and editorMode in a settings file answers for somebody who has never made one.

Vi editing has two modes over the same line. INSERT is the box everybody has. NORMAL takes a letter as an instruction, and a letter it has no instruction for does nothing at all rather than being typed. NORMAL opens two more for a while, VISUAL and REPLACE. Every session opens in INSERT, whichever style is in force, and the mode is drawn beneath the box beside the mode that says how much the session asks. The ordinary box is in neither mode, and nothing about a mode is drawn at it.

An instruction still waiting for its next key is drawn after the mode, as vi's showcmd draws it: NORMAL d once d is pressed, NORMAL di after the i, and the mode alone once the instruction is whole.

A key beginning one of vi's instructions that this box does not have does nothing, and nor does the key vi would give it: ", q, @, m, ', `, z, Z, [, ], g' and g` each take one more key, so ma sets no mark and opens no INSERT mode. g?, gq, gw and g@ take the stretch they would act on, so g?iw changes nothing. After an operator only ', `, [, ] and z take their key, as in vi, so dm ends the d and the key after it is read on its own. In VISUAL mode those four take no key, since the selection is the stretch, and R changes the rows the selection crosses.

Escape enters NORMAL mode and leaves the line exactly as it was. It also abandons an instruction still waiting for a key, so d, Escape, w moves a word rather than deleting one, and so does any other key that is not a character, such as an arrow or Enter. Discarding a half-typed line is still Ctrl-C. Ctrl-[ is the same request from a terminal that reports the modifier rather than sending the byte Escape already is. In the ordinary box Escape discards the line as it always has.

While a turn runs, Escape stops it only once the box has no use for the press:

The box	Escape
INSERT, VISUAL or REPLACE	enters NORMAL mode, and the turn keeps running
NORMAL, an instruction or a count waiting	abandons it, and the turn keeps running
NORMAL, nothing waiting	stops the turn

So the Escape you press out of habit after sending leaves INSERT, and a second one stops the turn. Ctrl-C stops the turn on the first press from any mode. A summary, an aside, a goal check and a manifest run take Escape the same way. A shell command takes no keys at the box, so Escape stops one from any mode. In the ordinary box Escape stops a turn on the first press.

Getting back into INSERT mode

Key	Where the caret lands
i, a	before or after the character the caret is on
I, A	the first character of the line, the end of the line
o, O	a new line below, a new line above

Leaving INSERT mode puts the caret on a character rather than past the end of the line, since in NORMAL mode it sits on the character the next instruction acts on.

! and ? are instructions in NORMAL mode rather than the marks that arm shell mode and put the key list up. Both are a press of i away. Reading ! as the mark would arm a shell from a press asking for something else, and there is no way out of a shell armed by accident except deleting back past the mark.

Typing over the line

R opens REPLACE mode, and the hint line says REPLACE. Each character you type takes the place of the one under the caret, until Escape takes you back to NORMAL mode. At the end of a row and on a marker the character goes in beside the caret instead, and Shift-Enter breaks the row without taking anything; Enter sends. Backspace puts back what the last character you typed took the place of, as far back as the R, and past that only moves the caret left. Ctrl-W and Ctrl-U do the same as far as the start of the word and of the row. u takes back everything typed since the R as one change. . does not repeat it, and a count in front of R does nothing.

Motions

Keys	Where the caret goes
h, l, Space	one character left or right
w, e, b, ge	the start of the next word, the end of this word or the next, the start of this word or the previous, the end of the word before
W, E, B, gE	the same four, where a word is a run of anything that is not a blank
0, $, ^	the first column, the last character, the first character that is not a blank
_	the first character that is not a blank, on the row a count names counting this one as the first
|	the column a count names, counting the first as one
gg, G	the first character that is not a blank on the first line of the input, and on the last
%	the bracket that pairs with the first one at or after the caret on this line
f, F, t, T then a character	the next or previous occurrence of it on this line, landing on it or stopping one short
;, ,	that jump again, and the same jump reversed

A jump looks only along the line the caret is on, and one that finds nothing leaves the caret where it was. w lands on the first character of the next word, rather than after the word it crossed where the word keys under Ctrl land.

% stays on the caret's line, where vi's crosses lines. It pairs ( with ), [ with ] and { with }, counting only brackets of the kind it found, and a bracket with no partner on the line leaves the caret where it was. A pair split over rows, a block pasted in with its closing brace three rows down, is j and f} away instead. The brackets a picture or paste is written with are not brackets to it. A count in front of % is spent and moves nothing.

w ends a word where punctuation begins, as vi does. In src/main.rs each name is a word and so are the slash and the dot, so dw on src takes src alone. W crosses the whole path in one press. A picture or paste is a word by itself to w, e, b and ge, and part of the word it touches to the capitals. An empty row is a stop for w, b and ge, so none of them crosses a paragraph break in one press.

k, j and / are the keys they spell rather than motions of their own. k and j are Up and Down: they walk the rows of a paragraph, then your prompt history, then the transcript, exactly as the arrows do. / opens the search Ctrl-R opens, that being the only search here. While a key is waiting for the character to jump to, every press is that character, so f/ jumps to a slash and fj to a j. A count in front of k or j is the other exception, and moves rows inside the input alone.

Counts

A number in front of an instruction says how many. 1 to 9 begin a count and every digit after one continues it, so 0 is still the key for the first column and 10l is ten characters. A count in front of an operator and one in front of its motion multiply, so 2d3w is d6w.

Keys	What the count says
3w, 5l, 2f,, 3;	how many times over the motion is meant
2G, 2gg, 2_	which row to go to, where _ counts the caret's row as the first
8|	which column to go to
3j, 3k	how many rows to move, inside the input and no further
3dd, d3w, 3x, 3X, 3~, 3rx, 3gUU, 3>>	how much of the stretch the operator takes
3p, 3J, 3gJ	how many copies go back, and how many rows end up as one
3.	how many the repeat is of, in place of the count it recorded
3u	how many changes to take back

The line bounds a count, not the number you type. A counted motion stops at the first step that moves nothing, so 999l reaches the end of the line, and an extent takes what there is, so 9dd on a two-row paragraph takes the two rows. p is the exception, since a copy always goes somewhere: it puts back as many as you asked for. r takes all of its count or nothing, so 5rx with two characters left changes neither. A counted change is one change and one step to undo.

The count is drawn after the mode with the rest of the instruction, so three presses are NORMAL 2d3. Escape abandons it, as it abandons any instruction still waiting for a key.

Operators

d takes a stretch out, c takes it out and opens INSERT mode where it was, y keeps it and leaves the line alone, > and < move every row the stretch reaches a step from or towards the margin, and gu, gU and g~ make it lower case, upper case or the other case. Each waits for the stretch to act on:

Keys	The stretch
a motion	from the caret to wherever that motion would take it
j, k, G, gg, _	every row from the caret's to the one the key reaches, whole
the operator's own letter doubled	the whole line: dd, and guu or gugu
D, C, x, s	to the end of the line, and the character under the caret
X	the character before the caret
Y, S	the whole line

~ changes the case of the character under the caret and moves on, so pressing it again walks along the line. r or gr then a key makes the character under the caret that key, and 3rx makes three of them x. r then Enter is the Enter alone, where vi would break the line, since Enter abandons a key still waiting. Case changes as vim changes it: gUiw over Straße is STRASSE, and a letter with no capital of its own, such as the ff ligature, stays as it is.

So dw, cw and yw are one idea rather than three bindings, and d$ and dG work without being listed. Whether the character a motion landed on is taken depends on the motion, as it does in vi: de takes the word's last letter where dw stops before the next word's first, and cw on a character that is not a blank behaves as ce, leaving the space after the word. cW is cE in the same way, and on the last character of a word either changes that character alone. dw on the last word of a row takes the word and leaves the newline. dge takes both ends: the last letter of the word before, and the character the caret was on. d% takes both brackets and everything between them, from either bracket, and d| stops short of the column, so d| is d0. d_ is dd, and d3_ is 3dd.

p and P put the register back after and before the caret, and a stretch that was whole lines comes back as a line of its own. J makes this line and the one below into one, with a single space where the newline was. gJ joins them with nothing there and leaves the blanks the next line began with, for a line broken in the middle of a word or a path.

u puts back what the last change took, and pressed again the change before that, as far back as a thousand changes, the same depth as vim's. Everything typed in INSERT mode after c or one of the keys that open it is one change with the key, so one u takes back o's new row and all you typed on it. Sending, clearing or putting away the line leaves nothing to undo, and so does a line the box is handed whole, such as a recalled prompt. There is no redo: Ctrl-R is the prompt search.

. does the last change again at the caret. After c, s, S, C, i, a, I, A, o or O that includes what you typed, so cw, X, Escape, w, . changes the next word to X as well, and p, P, J and gJ are made again too. It does nothing after typing that attached something, whether a picture, a paste the box folded into a marker or an @ name, since doing it again would attach the same thing twice, and nothing after a completion you chose from a list. It does nothing either after a put, a join, r or a case change over a selection, d or c over a selection made with v rather than V, or typing over the line with R.

The register is vi's unnamed one and the only one. It is not the system clipboard, which Ctrl-V owns and which you share with every other window you have open, so a yank here does not travel out of the box. Only d, c, y, the keys spelled from them and p over a selection fill it: a shift, a case change and r leave what you yanked there to put back.

Text objects

After an operator, i and a say the stretch is a thing rather than a distance, and the next press says which: w a word, W a run of anything that is not a blank, and a quote or either half of a bracket pair for what lies between them, with b for the round pair and B for the curly one, as in vi. i takes what is inside and a takes what surrounds it too. All on the line the caret is on.

ci( is what you mean when you want the arguments replaced, and it works with the caret on the name in front of the bracket, where it usually is: a pair is the one enclosing the caret, or else the next one along the line. Either half names it, so di( and di) are the same request.

w treats punctuation as a word of its own, so in src/main.rs the slashes belong to neither name. W is the same thing with punctuation folded in, which is why aW takes the whole path.

Marking a stretch out first

v marks a stretch out character-wise and V line-wise, and the whole of it is drawn while you choose it, on every row it crosses. That is the point of having both this and an operator waiting for a motion: the stretch is on the screen while it is being chosen, and the next key acts on it.

An operator here needs no extent: x is d and s is c, r replaces every selected character with one, and ~, u and U change the case, as do g~, gu and gU. The capitals act on every row the selection crosses, whole: D and X take them, Y keeps them, and C, S and R change them. After any of those but Y, or after d, c, > or < over a line-wise selection, . does it again to as many rows from the caret. Motions move the end the caret is at, and a count moves it further, so v2j marks three rows. o puts the caret at the other end, and a text object becomes the selection.

p puts what you yanked where the selection is and keeps what the selection held, so pressing p over another stretch swaps the two. P does the same and keeps what you yanked, to put one yank over several stretches. A yanked row stays a row, splitting the line when you put it over part of one.

The key that opened the mode closes it, the other of the two changes which kind is in force, and Escape abandons the selection. Every operator ends it, so nothing acts on a stretch that is no longer drawn.

gv marks the last selection out again, however it ended, with each end at the row and the column it was at, so V> and then gv> shifts the same rows twice. In VISUAL mode gv swaps the selection on the screen for the one before.

A selection is character-wise or line-wise and never a rectangle. A box ten rows tall holding one prompt is not where somebody edits columns.

These keys and a marker

A marker is one thing to every key above. A motion crosses it whole and leaves the caret nowhere inside it. An operator takes it whole or not at all, and taking it takes the attachment off. r over one does nothing, over a selection or not: replacing the text either side and leaving the marker standing would be a line nobody could read. A case change goes around one and leaves it as it was, since a marker spelled in capitals would name no picture.