Direct mode

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by PZ0151 (talk | contribs) at 14:51, 2 May 2020 (Direct mode in 'Integrated development environments' added.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Direct mode, also known as immediate mode[1][2] is a computing term referring to the input of textual commands outside the context of a program. The command would be executed immediately and the results printed on screen, in contrast to programming mode where nothing would be executed until a specific command was given. (BASIC's RUN is an example of a direct mode command.) Some commands could be used in either mode, while others were exclusive to one or the other.

Direct mode was most often used on 8-bit systems such as the Commodore 64 and Atari 800 series, though commands entered at a Unix shell can be thought of as direct mode equivalents to shell scripts, and modern interpreted languages like Python and Perl include REPL shells where commands may be entered for immediate evaluation and execution.

Also modern Integrated development environments often offer a direct mode, where during debugging and while the program execution is stopped, commands can be executed directly in the current scope and the result is displayed on the monitor.

Example

Non-direct mode:

10 PRINT "HELLO WIKIPEDIA"
READY.
RUN
HELLO WIKIPEDIA
READY.

Direct mode:

PRINT "HELLO WIKIPEDIA"
HELLO WIKIPEDIA
READY.

See also

References

  1. ^ "Immediate Mode" (PDF).
  2. ^ "C128 System Guide: Section 3".