{"schemaVersion":1,"contentVersion":"3.4.0","id":"intermediate.13","languages":{"javascript":{"id":"intermediate.13","title":"Edit a rectangle","moduleName":"Repeat, select and compose","tips":"","concept":"

Apply a column edit and understand when Escape commits it.

Before this lesson: Visual selection; insertion.

Ctrl-v selects a rectangle. I inserts a prefix across its selected lines after Esc; A appends to its right edge. Within a block, $ then A handles each selected line’s actual end. Unequal lengths matter. If the browser intercepts Ctrl-v, use Keyboard check; do not assume native and browser shortcuts are identical.

Example

Select the first column of three notes with Ctrl-v then 2j. I, type a bullet and a space, then Esc adds the prefix to all selected lines.

Use Reset to try again.

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Apply a column edit and understand when Escape commits it.

Before this lesson: Visual selection; insertion.

Ctrl-v selects a rectangle. I inserts a prefix across its selected lines after Esc; A appends to its right edge. Within a block, $ then A handles each selected line’s actual end. Unequal lengths matter. If the browser intercepts Ctrl-v, use Keyboard check; do not assume native and browser shortcuts are identical.

Example

Select the first column of three notes with Ctrl-v then 2j. I, type a bullet and a space, then Esc adds the prefix to all selected lines.

Use Reset to try again.

","teaches":["visual:"],"introduces":["","I","A","$","count"],"constraints":[],"drills":[{"task":"Prefix all three notes with the shown marker.","hint":"Compare the complete target, including spaces, delimiters and protected lines. Undo is available.","mode":"python","start":"# first note\n# a longer note\n# last note","startCursor":{"line":0,"ch":0},"paths":[{"keys":["","2","j","I","# ",""],"tier":"idiomatic","technique":"visual:","core":["visual:"],"note":"A rectangular change settles on Escape. An end-of-line block handles different lengths rather than a fixed right column."}],"target":"# # first note\n# # a longer note\n# # last note","language":"python","evidence":"guided","canonicalKey":"intermediate.13#0","canonicalFingerprint":"v2lo11"}]},"text":{"id":"intermediate.13","title":"Edit a rectangle","moduleName":"Repeat, select and compose","tips":"","concept":"

Apply a column edit and understand when Escape commits it.

Before this lesson: Visual selection; insertion.

Ctrl-v selects a rectangle. I inserts a prefix across its selected lines after Esc; A appends to its right edge. Within a block, $ then A handles each selected line’s actual end. Unequal lengths matter. If the browser intercepts Ctrl-v, use Keyboard check; do not assume native and browser shortcuts are identical.

Example

Select the first column of three notes with Ctrl-v then 2j. I, type a bullet and a space, then Esc adds the prefix to all selected lines.

Use Reset to try again.

","teaches":["visual:"],"introduces":["","I","A","$","count"],"constraints":[],"drills":[{"task":"Prefix all three notes with the shown marker.","hint":"Compare the complete target, including spaces, delimiters and protected lines. Undo is available.","mode":"text/plain","start":"first note\na longer note\nlast note","startCursor":{"line":0,"ch":0},"paths":[{"keys":["","2","j","I","- ",""],"tier":"idiomatic","technique":"visual:","core":["visual:"],"note":"A rectangular change settles on Escape. An end-of-line block handles different lengths rather than a fixed right column."}],"target":"- first note\n- a longer note\n- last note","language":"text","evidence":"guided","canonicalKey":"intermediate.13#0","canonicalFingerprint":"v2lo11"}]}}}