Editor

Source code editor in pure Go.

• This is a know-what-you're-doing source code editor
• As the editor is being developed, the rules of how the UI interacts will become more well defined.

Features

• Auto-indentation of wrapped lines.
• No code coloring (except comments).
• Many TextArea utilities: undo/redo, replace, comment, ...
• Start external processes from the toolbar with a click, capturing the output to a row.
• Drag and drop files/directories to the editor.
• Detects if files opened are changed outside of the editor.
• Calls goimports if available when saving a .go file.
• Clicking on .go files identifiers will jump to the identifier definition (Ex: a function definition).
• Auto-completion (suggestions) in .go files. (experimental)
• Debugger utility for go programs. (experimental)

Installation and usage

go get -u github.com/jmigpin/editor
cd $GOPATH/src/github.com/jmigpin/editor
go build 
./editor

Usage of ./editor:
  -colortheme string
    	available: light, dark, acme (default "light")
  -commentscolor int
    	Colorize comments. Can be set to zero to use a percentage of the font color. Ex: 0=auto, 1=Black, 0xff0000=red.
  -cpuprofile string
    	profile cpu filename
  -dpi float
    	monitor dots per inch (default 72)
  -font string
    	font: regular, medium, mono, or a filename (default "regular")
  -fonthinting string
    	font hinting: none, vertical, full (default "full")
  -fontsize float
    	 (default 12)
  -scrollbarleft
    	set scrollbars on the left side (default true)
  -scrollbarwidth int
    	Textarea scrollbar width in pixels. A value of 0 takes 3/4 of the font size.
  -sessionname string
    	open existing session
  -shadows
    	shadow effects on some elements (default true)
  -tabwidth int
    	 (default 8)
  -usemultikey
    	use multi-key to compose characters ([multi-key, ~, a]=ã, ...)
  -wraplinerune int
    	code for wrap line rune, can be set to zero (default 8594)

Basic Layout

The editor has a top toolbar and columns. Columns have rows. Rows have a toolbar and a textarea.

These row toolbars are also textareas where clicking on the text will run that text as a command.

The row toolbar has a square showing the state of the row.

Toolbar usage examples

Commands in toolbars are separated by "|" (not to be confused with the shell pipe). If a shell pipe is needed it should be escaped with a backslash.

All commands implemented by the editor start with an Uppercase letter. Otherwise it tries to run an existent external program.

Examples:

• ~/tmp/subdir/file1.txt | ls Clicking at ls will run ls at ~/tmp/subdir
• ~/tmp/subdir/file1.txt | ls -l \| grep fi Notice how "|" is escaped, allowing to run ls -l | grep fi
• ~/tmp/subdir/file1.txt Clicking at file1.txt opens a new row to edit the same file. Clicking at ~/tmp opens a new row located at that directory.
• gorename -offset $edPosOffset -to abc Usage of external command with active row position as argument. gorename godoc, go tools.
• guru -scope fmt callers $edPosOffset Usage of external command with active row position as argument. guru godoc, go tools.
• grep -niIR someword Grep results with line positions that are clickable.
• xdg-open $edDir Open favorite external application with active row directory.
• xterm Open an xterm at the active row directory.

Commands

Top toolbar commands

• ListSessions: lists saved sessions
• SaveSession <name>: save session to ~/.editor_sessions.json
• DeleteSession <name>: deletes the session from the sessions file
• NewColumn: opens new column
• NewRow: opens new empty row located at the active-row directory, or if there is none, the current directory. Useful to run commands in a directory.
• ReopenRow: reopen a previously closed row
• SaveAllFiles: saves all files
• ReloadAll: reloads all filepaths
• ReloadAllFiles: reloads all filepaths that are files
• ColorTheme: cycles through available color themes.
• FontTheme: cycles through available font themes.
• Exit: exits the program

Row toolbar commands

These commands run on a row toolbar, or on the top toolbar with the active-row.

• Save: save file
• Reload: reload content
• CloseRow: close row
• CloseColumn: closes row column
• Find: find string (ignores case)
• GotoLine <num>: goes to line number
• Replace <old> <new>: replaces old string with new, respects selections
• Stop: stops current process (external cmd) running in the row
• ListDir: lists directory
  • -sub: lists directory and sub directories
  • -hidden: lists directory including hidden
• MaximizeRow: maximize row. Will push other rows up/down.
• CopyFilePosition: copy to clipboard/primary the cursor file position in the format "file:line:col". Useful to paste a clickable text with the file position.
• ToggleRowHBar: toggles row textarea horizontal scrollbar.
• XdgOpenDir: calls xdg-open to open the row directory with the preferred external application (ex: a filemanager).
• GoRename <new-name>: calls gorename to rename the identifier under the text cursor. Uses the row/active-row filename, and the cursor index as the "offset" argument. Reloads the calling row at the end if there are no errors.
• GoDebug {run,test} <filename.go>: debugger utility for go programs.
  • -dirs: directories to include in the debug session.
  • use esc key to stop the debug session.
• toolbar first part (usually the row filename): clicking on a section of the path of the filename will open a new row (possibly duplicate) with that content. Ex: if a row filename is "/a/b/c.txt" clicking on "/a" will open a new row with that directory listing, while clicking on "/a/b/c.txt" will open a duplicate of that file.

Textarea commands

• OpenSession <name>: opens previously saved session
• <url>: opens url in preferred application.
• <filename(:number?)(:number?)>: opens filename, possibly at line/column (usual output from compilers). Check common locations like $GOROOT and C include directories.
• <identifier-in-a-.go-file>: opens definition of the identifier. Ex: clicking in Println on fmt.Println will open the file at the line that contains the Println function definition.

Environment variables set available to external commands

• $edName: row name.
• $edDir: row directory.
• $edPosOffset: filename with offset position from active row cursor. Ex: "filename:#123".

Row states

• background colors:
  • blue: row file has been edited.
  • orange: row file doesn't exist.
• dot colors:
  • black: row currently active. There is only one active row.
  • red: row file was edited outside (changed on disk) and doesn't match last known save. Use Reload cmd to update.
  • blue: there are other rows with the same filename (2 or more).
  • yellow: there are other rows with the same filename (2 or more). Color will change when the pointer is over one of the rows.

Key/button shortcuts

Global key/button shortcuts

• esc:
  • close context float box
  • stop debugging session
• f1: toggle context float box (work in progress)
  • does auto-completion in .go files.

Column key/button shortcuts

• buttonLeft:
  • on left border: drag to move/resize
  • on square-button: close

Row key/button shortcuts

• ctrl+s: save file
• ctrl+f: warp pointer to "Find" cmd in row toolbar
• buttonLeft on square-button: close row
• on top border:
  • buttonLeft: drag to move/resize row
  • buttonMiddle: close row
  • buttonWheelUp: adjust row vertical position, pushing other rows up
  • buttonWheelDown: adjust row vertical position, pushing other rows down
• Any button/key press: make row active to layout toolbar commands

Textarea key/button shortcuts

• left: move cursor left
• right: move cursor right
• up: move cursor up
• down: move cursor down
• home: start of line
• end: end of line
• delete: delete current rune
• backspace: delete previous rune
• pageUp: page up
• pageDown: page down
• tab (if selection is on): insert tab at beginning of lines
• shift+left: move cursor left adding to selection
• shift+right: move cursor right adding to selection
• shift+up: move cursor up adding to selection
• shift+down: move cursor down adding to selection
• shift+home: start of string adding to selection
• shift+end: end of string adding to selection
• shift+tab: remove tab from beginning of line
• ctrl+a: select all
• ctrl+c: copy to clipboard
• ctrl+d: comment lines
• ctrl+k: remove lines
• ctrl+v: paste from clipboard
• ctrl+x: cut
• ctrl+z: undo
• ctrl+alt+down: move line down
• ctrl+alt+shift+down: duplicate lines
• ctrl+shift+z: redo
• ctrl+shift+d: uncomment lines
• buttonLeft: move cursor to point
  • drag: selects text - works as copy making it available for paste (primary selection).
  • over a debug annotation: print the shortened annotation string.
• buttonMiddle: paste from primary
• buttonRight: move cursor to point + text area cmd
• buttonWheelUp: scroll up
• buttonWheelDown: scroll down
• buttonWheelUp on scrollbar: page up
• buttonWheelDown on scrollbar: page down
• shift+buttonLeft: move cursor to point adding to selection
• ctrl+buttonLeft:
  • godebug: select annotation
• ctrl+buttonWheelUp:
  • godebug: show previous debug step
  • on textarea: show previous debug step
  • over a debug annotation: show same line previous annotation
• ctrl+buttonWheelDown:
  • godebug: show next debug step
  • on textarea: show next debug step
  • over a debug annotation: show same line next annotation

Notes

• Uses X shared memory extension (MIT-SHM).
• MacOS might need to have XQuartz installed.
• Notable projects that inspired many features:
  • Oberon OS: https://www.youtube.com/watch?v=UTIJaKO0iqU
  • Acme editor: https://www.youtube.com/watch?v=dP1xVpMPn8M