Thomson-Davis Editor

{{Infobox software

| name = TDE

| logo =

| screenshot = Tde.png

| caption = Screenshot of TDE in console (DOS/Unix)

| developer = Eric Pement; maintenance by Jason Hood

| released =

| latest release version = 5.1v

| programming language = C

| operating system = DOS, Windows, Unix-like

| platform = Cross-platform

| genre = Text editor

| license = Public domain

| website = http://www.pement.org/tde.htm

}}

TDE (Thomson–Davis Editor), also called the TDE programmer's editor, is a public-domain, cross-platform, console-mode text editor written in C. It targets programmers and technical writers, and runs under DOS, Windows (Win32/Cygwin), and Unix-like systems.{{cite web|title=TDE by Eric Pement|url=http://www.pement.org/tde.htm|accessdate=2025-06-13}}{{Cite web |title=TDE, the Thomson-Davis Editor |url=http://adoxa.altervista.org/tde/ |access-date=2025-06-13 |website=adoxa.altervista.org}}

History and development

TDE was created by Eric Pement and released into the public domain, later mainteined by Jason Hood.{{cite web|title=Why I like TDE|url=http://www.pement.org/tde.htm|accessdate=2025-06-13}}

Features

TDE provides a range of console-oriented editing capabilities:

Console-mode operation – no GUI required
Keyboard remapping, with custom keymaps including WordStar-style bindings
Macros for automating editing tasks
Drawing mode using IBM OEM line-drawing characters
Resizable block to measure string width
Window splitting and two-file comparison with synchronized scrolling
Syntax highlighting with user-definable lexers
Custom help menus editable by users
Change tracking – flags unsaved edits

Reception

Users value TDE for its lightweight nature, portability, and rich console-based features. One user described it as "powerful and light and infinitely customisable". Eric Pement places TDE second in his personal use, just behind GNU Emacs{{cite web|title=Text Editors - Eric Pement|url=http://www.pement.org/editors.htm|accessdate=2025-06-13}}.

Comparison

TDE differentiates itself from GUI editors like Notepad++ or UltraEdit by operating entirely in console environments. It shares use-case similarities with vi and Emacs, but is distinct in its keyboard customizability and multi-file compare tool.