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qtutils (version 0.1-3)

qrepl: A Qt based REPL emulator

Description

Creates a Qt Widget that emulates the R REPL.

Usage

qrepl(env = .GlobalEnv, ..., family = "monospace", pointsize = 12, incolor = "red", outcolor = "blue", msgcolor = "black", html.preferred = FALSE, history = TRUE, title)
qreplu(env = .GlobalEnv, ..., history = TRUE, eval.on.newline = TRUE, incolor = "red", outcolor = "blue", msgcolor = "black")

Arguments

env
The evaluation environment for the REPL.
...
Further arguments, passed on to RCodeEditor.
family
Font family to be used.
pointsize
Font pointsize to be used.
incolor
The color used for code that is evaluated.
outcolor
The color used for output.
msgcolor
The color used for messages.
html.preferred
Logical flag indicating whether HTML output is preferred (for table-like objects).
history
Logical flag indicating whether command history should be available. If enabled, pressing Ctrl+Up or Down arrows allow navigation through previous commands. History is currently not retained across invocations.
title
Character string giving window title.
eval.on.newline
Logical flag indicating whether execution should be attempted whenever Enter is pressed. Otherwise execution must be explicitly triggered, e.g., by pressing the Ctrl+Enter shortcut.

Value

Details

This widget tries to emulate the behaviour of the R command-line interface (Read-Eval-Print-Loop) in a GUI. The current implementation is essentially a proof-of-concept, and not meant for serious use.

Two versions are available. qreplu emulates the conventional REPL interface where commands are typed at a command prompt and evaluated when Enter is pressed (except that parse errors are trapped and not evaluated). qrepl provides an alternative interface with two command specification modes and a common output area. Commands can be entered either in input mode, where one or more commands may be typed and then executed using Ctrl+Enter, or in edit mode, where commands are typed in a file, and selections may be executed similarly. The latter mode is intended to facilitate the recommended method of working in ESS, where commands are entered and modified within an editor, and executed as necessary. When working in edit mode, commands executed are automatically added to the editor area, keeping a record of those commands.

All code editing interfaces support command completion and code indentation (but the rules are not yet customizable).