REPL
Read-Eval-Print Loop (REPL) environment.
A Read-Eval-Print Loop (REPL) environment is an interactive programming environment which takes individual user inputs (e.g., single expressions), evaluates those inputs, and returns the result. Accordingly, a program written in a REPL environment is executed piecewise and sequentially.
REPL environments find common use in exploratory programming, prototyping, and debugging.
The REPL environment exposed here is available both as a standalone application and as a library which is embeddable in other libraries and applications.
Usage
var REPL = require( '@stdlib/repl' );
REPL( [options] )
Returns a REPL
instance.
// Create a new REPL:
var repl = new REPL();
// ...
// Close the REPL:
repl.close();
The function accepts the following options
:
- input: input (readable) stream. Default:
stdin
. - output: output (writable) stream. Default:
stdout
. - sandbox: boolean indicating whether to run a REPL in a sandboxed context. Default:
false
. - timeout: number of milliseconds to execute a command before terminating execution. Default:
4294967295
. - isTTY: boolean indicating whether the input and output streams should be treated like a TTY (terminal) and whether the REPL should use ANSI/VT100 escape codes when writing to the output stream.
- inputPrompt: input prompt. If the input prompt includes the character sequence
%d
, the input prompt includes line numbers. Default:'In [%d]: '
. - outputPrompt: output prompt. If the output prompt includes the character sequence
%d
, the output prompt includes line numbers. Default:'Out[%d]: '
. - welcome: welcome message.
- padding: number of empty lines between consecutive commands. Default:
1
. - themes: table containing color themes for syntax highlighting.
- load: file path specifying a JavaScript file to load and evaluate line-by-line (e.g., a previous REPL history file).
- save: file path specifying where to save REPL command history.
- log: file path specifying where to save REPL commands and printed output.
- quiet: boolean indicating whether log information, confirmation messages, and other possible REPL diagnostics should be silenced. Default:
false
. - settings: object specifying REPL settings.
The function supports specifying the following settings:
- autoClosePairs: boolean indicating whether to automatically insert matching brackets, parentheses, and quotes. Default:
true
. - autoDeletePairs: boolean indicating whether to automatically delete adjacent matching brackets, parentheses, and quotes. Default:
true
. - autoPage: boolean indicating whether to automatically page return values having a display size exceeding the visible screen. When streams are TTY, the default is
true
; otherwise, the default isfalse
. - bracketedPaste: boolean indicating whether to enable bracketed-paste mode. When streams are TTY, the default is
true
; otherwise, the default isfalse
. - autoDisableBracketedPasteOnExit: boolean indicating whether to automatically disable bracketed-paste upon exiting the REPL. When streams are TTY and bracketed paste is enabled, the default is
true
; otherwise, the default isfalse
. - completionPreviews: boolean indicating whether to display completion previews for auto-completion. When streams are TTY, the default is
true
; otherwise, the default isfalse
. - syntaxHighlighting: boolean indicating whether to enable syntax highlighting of entered input expressions. When streams are TTY, the default is
true
; otherwise, the default isfalse
. - theme: initial color theme for syntax highlighting. Default:
stdlib-ansi-basic
.
REPL.prototype.viewport()
Returns the REPL viewport.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// Query the REPL viewport:
var v = repl.viewport();
// Close the REPL:
repl.close();
REPL.prototype.createContext()
Returns a REPL context.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Return a new REPL context:
var ctx = repl.createContext();
// ...
// Close the REPL:
repl.close();
REPL.prototype.resetContext()
Resets a REPL's execution context.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Reset the REPL context:
repl.resetContext();
// ...
// Close the REPL:
repl.close();
REPL.prototype.clearHistory()
Clears a REPL's history.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Clear the REPL history:
repl.clearHistory();
// ...
// Close the REPL:
repl.close();
REPL.prototype.clearUserDocs()
Clears user-defined documentation.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Clear user-defined documentation:
repl.clearUserDocs();
// ...
// Close the REPL:
repl.close();
REPL.prototype.themes()
Returns a list of all available themes for syntax highlighting.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Fetch all available themes:
var themes = repl.themes();
// returns [...]
// ...
// Close the REPL:
repl.close();
REPL.prototype.getTheme( name )
Returns a theme's color palette for syntax highlighting.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Add a user-defined theme:
repl.addTheme( 'myTheme', {
'keyword': 'red'
});
// Get a theme's color palette:
var theme = repl.getTheme( 'myTheme' );
// returns { 'keyword': 'red' }
// ...
// Close the REPL:
repl.close();
REPL.prototype.addTheme( name, theme )
Adds a syntax highlighting theme.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Add a user-defined theme:
repl.addTheme( 'myTheme', {
'keyword': 'red',
'variable': 'green'
// ...
});
// ...
// Close the REPL:
repl.close();
The syntax-highlighter supports the following tokens and associated theme fields:
- keyword: keywords (e.g.,
var
,function
,let
,const
,in
, andclass
). - control: control flow keywords (e.g.,
if
,else
,try
,catch
, andreturn
). - specialIdentifier: special identifiers (e.g.,
this
andsuper
). - string: string and template literals.
- number: numeric literals.
- literal: reserved literals (e.g.,
true
,false
,null
, andundefined
). - regexp: regular expressions.
- command: built-in REPL commands.
- function: function identifiers.
- object: object identifiers.
- variable: literal identifiers.
- name: variable names.
- comment: line comments.
- punctuation: punctuation symbols (e.g.,
;
,[
,{
,,
, and?
). - operator: operator symbols (e.g.,
+
,-
,*
,=
,++
,>=
, and&&
).
REPL.prototype.deleteTheme( name )
Deletes a specified theme from the syntax-highlighter.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Add a user-defined theme:
repl.addTheme( 'myTheme', {
'keyword': 'red',
'variable': 'green'
// ...
});
// Delete the added theme:
repl.deleteTheme( 'myTheme' );
// ...
// Close the REPL:
repl.close();
REPL.prototype.renameTheme( oldName, newName )
Renames a specified theme in the syntax-highlighter.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Add a user-defined theme:
repl.addTheme( 'myTheme', {
'keyword': 'red',
'variable': 'green'
// ...
});
// Rename the added theme:
repl.renameTheme( 'myTheme', 'yourTheme' );
// ...
// Close the REPL:
repl.close();
REPL.prototype.load( fpath, clbk )
Loads and evaluates a JavaScript file line-by-line.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Load and evaluate a file line-by-line:
repl.load( './path/to/file.js', done );
function done() {
// Close the REPL:
repl.close();
}
REPL.prototype.reset()
Resets a REPL.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Reset the REPL:
repl.reset();
// ...
// Close the REPL:
repl.close();
REPL.prototype.clear()
Clears the entire REPL screen and scrollback history.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Clear the REPL:
repl.clear();
// ...
// Close the REPL:
repl.close();
This method is only applicable for TTY REPLs. In non-TTY REPLs, this method is a non-operation.
REPL.prototype.clearLine()
Clears the current line.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Clear the current line:
repl.clearLine();
// ...
// Close the REPL:
repl.close();
This method is only applicable for TTY REPLs. In non-TTY REPLs, this method is a non-operation.
REPL.prototype.clearCommand()
Clears the current REPL command buffer (i.e., clear any command which has been buffered but not yet executed).
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Clear the command buffer:
repl.clearCommand();
// ...
// Close the REPL:
repl.close();
REPL.prototype.settings( [name[, value]] )
Returns REPL settings.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Retrieve REPL settings:
var o = repl.settings();
// ...
// Close the REPL:
repl.close();
To retrieve the current value for a specific setting, provide a name
argument.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Retrieve current setting value:
var v = repl.settings( 'autoClosePairs' );
// ...
// Close the REPL:
repl.close();
To update a specific setting, provide a value
argument.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Update setting value:
repl.settings( 'autoClosePairs', false );
// ...
// Close the REPL:
repl.close();
REPL.prototype.close()
Closes a REPL.
var debug = require( '@stdlib/streams/node/debug-sink' );
// Create a new REPL:
var repl = new REPL({
'output': debug()
});
// ...
// Close the REPL:
repl.close();
Commands
REPL instances support the following commands...
addTheme( name, theme )
Adds a syntax highlighting color theme.
// Add color theme:
In [1]: addTheme( 'myTheme', { 'keyword': 'red' } )
// Check updated list of themes:
In [2]: themes()
Out[2]: [ 'stdlib-ansi-basic', 'myTheme' ]
alias2pkg( arg )
Returns the package name associated with a provided alias or class instance.
In [1]: var v = alias2pkg( 'base.sin' )
Out[1]: '@stdlib/math/base/special/sin'
Note: only direct instances of documented built-in constructors are supported.
alias2related( arg )
Returns aliases related to a specified alias or class instance.
In [1]: var v = alias2related( 'base.sin' )
Out[1]: [...]
Note: only direct instances of documented built-in constructors are supported.
ans
Result of the last successfully executed command.
In [1]: identity( 3.14 )
Out[1]: 3.14
In [2]: ans
Out[2]: 3.14
assignfrom( workspace, variable )
Reads a value from a specified workspace
.
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
In [3]: workspace( 'barfoo' );
In [4]: var y = assignfrom( 'foobar', 'x' )
Out[4]: 3.14
assignin( workspace, variable, value )
Assigns a value
to a variable
in a specified workspace
.
In [1]: assignin( 'base', 'x', 3.14 );
In [2]: x
Out[2]: 3.14
citation()
Prints how to cite stdlib in publications.
In [1]: citation()
clear()
Clears the entire REPL screen and scrollback history.
In [1]: clear()
Note: this function is only applicable for TTY REPLs. In non-TTY REPLs, this function is a non-operation.
clearHistory()
Clears the REPL history.
In [1]: clearHistory()
clearUserDocs( [options] )
Deletes user-defined documentation.
In [1]: clearUserDocs()
The function supports the following options
:
include: inclusion filter. May be either an array-like
object
or a regular expression.exclude: exclusion filter. May be either an array-like
object
or a regular expression.filter: filter type. This option is only applicable for array-like
object
filters. Must be one of the following values:'alias'
: filter based on documentation alias. If a filter matches a documentation alias, the user-defined documentation is removed.'value'
: filter based on object reference. If a filter matches an associated object reference, the user-defined documentation is removed.'*'
: filter based on both documentation alias and object reference. If a filter matches either a documentation alias or an associated object reference, the user-defined documentation is removed.
Default:
'*'
.
In [1]: clearUserDocs( { 'include': /^foo/ } )
clearvars( [options] )
Deletes user-defined variables in the current workspace.
In [1]: clearvars()
The function supports the following options
:
- include: variable name inclusion filter. May be either an array-like
object
or a regular expression. - exclude: variable name exclusion filter. May be either an array-like
object
or a regular expression.
In [1]: clearvars( { 'include': /^foo/ } )
clearWorkspace( [name, ][options] )
Deletes user-defined variables in a specified workspace.
In [1]: clearWorkspace()
By default, the function clears user-defined variables in the current workspace. To clear user-defined variables in a different workspace, provide a workspace name
.
// Create a new workspace:
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
// Switch to another workspace:
In [3]: workspace( 'barfoo' );
In [4]: typeof x
Out[4]: 'undefined'
// List the variables in the previous workspace:
In [5]: varsWorkspace( 'foobar' )
Out[5]: [ 'x' ]
// Delete the variables in the previous workspace:
In [6]: clearWorkspace( 'foobar' );
In [7]: varsWorkspace( 'foobar' )
Out[7]: []
// Navigate to the previous workspace:
In [8]: workspace( 'foobar' );
// Confirm that the variables were deleted:
In [9]: x
Error: x is not defined
The function supports the following options
:
- include: variable name inclusion filter. May be either an array-like
object
or a regular expression. - exclude: variable name exclusion filter. May be either an array-like
object
or a regular expression.
In [1]: clearWorkspace( 'foobar', { 'include': /^x/ } );
contributors()
Prints a list of stdlib contributors.
In [1]: contributors()
copyright()
Prints copyright information.
In [1]: copyright()
credits()
Prints credits.
In [1]: credits()
currentWorkspace
Returns the name of the current workspace.
In [1]: currentWorkspace
Out[1]: 'base'
deleteTheme( name )
Deletes a syntax highlighting color theme.
// Add a color theme:
In [1]: addTheme( 'myTheme', { 'keyword': 'red' } )
// Check list of themes:
In [2]: themes()
Out[2]: [ 'stdlib-ansi-basic', 'myTheme' ]
// Delete the added theme:
In [3]: deleteTheme( 'myTheme' )
// Check updated list of themes:
In [4]: themes()
Out[4]: [ 'stdlib-ansi-basic' ]
deeprerequire( id )
Re-imports a module, JSON, or local file and all of its associated module dependencies.
In [1]: var foo = require( './foo.js' );
// Modify `./foo.js` and/or its module dependencies...
// Re-import the module:
In [2]: foo = deeprerequire( './foo.js' );
Modules can be imported from node_modules
. Local modules and JSON files can be imported using a relative path (e.g., './foo.js'
, './../bar.json'
, etc) that will be resolved against the current working directory.
deleteWorkspace( [name] )
Deletes a workspace.
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
In [3]: workspace( 'barfoo' );
In [4]: workspaces()
Out[4]: [ 'base', 'foobar', 'barfoo' ]
In [5]: deleteWorkspace( 'foobar' );
In [6]: workspaces()
Out[6]: [ 'base', 'barfoo' ]
If not provided an argument, the REPL deletes the current workspace and switches to the 'base'
workspace.
In [1]: workspace( 'foobar' );
In [2]: currentWorkspace
Out[2]: 'foobar'
In [3]: deleteWorkspace();
In [4]: workspaces()
Out[4]: [ 'base' ]
In [5]: currentWorkspace
Out[5]: 'base'
Note: the 'base'
workspace cannot be deleted.
donate()
Prints donation information.
In [1]: donate()
evalin( workspace, expression )
Evaluates an expression
in a specified workspace
.
// Create a workspace:
In [1]: workspace( 'foobar' );
// Create and switch to another workspace:
In [2]: workspace( 'barfoo' );
// Attempt to evaluate an expression in the first workspace:
In [3]: evalin( 'foobar', 'var x = 3.14;' );
// Check that nothing has changed in the current workspace:
In [4]: x
Error: x is not defined
// Switch to the first workspace:
In [5]: workspace( 'foobar' );
// Check that the expression was successfully evaluated:
In [6]: x
Out[6]: 3.14
example( arg )
Runs examples for a specified alias, property, or class instance.
In [1]: example( base.sin )
Note: only direct instances of documented built-in constructors are supported.
getTheme( [name] )
Returns a syntax highlighting color theme.
// Add a color theme:
In [1]: addTheme( 'myTheme', { 'keyword': 'red' } )
// Get the color theme:
In [2]: getTheme( 'myTheme' )
Out[2]: { 'keyword': 'red' }
Note: if no theme name is provided, the current theme is returned.
help( [arg] )
Prints help text.
In [1]: help()
To print help text for an alias,
In [1]: help( 'base.sin' )
In [2]: help( base.sin )
To print help text for a property,
In [1]: help( random.streams.randu.factory )
To print help text for a class instance,
In [1]: var x = new Float64Array( 10 );
In [2]: help( x )
Note: only direct instances of documented built-in constructors are supported.
info( arg )
Prints abbreviated help text for a provided alias, property, or class instance.
In [1]: info( base.sin )
In [2]: info( 'base.sin' )
Note: only direct instances of documented built-in constructors are supported.
isKeyword( keyword )
Returns a boolean
indicating whether a string is a reserved keyword in the REPL environment.
In [1]: isKeyword( 'base.sin' )
Out[1]: true
license()
Prints license information.
In [1]: license()
load( fpath )
Loads and evaluates a JavaScript file, such as a REPL history file, line-by-line.
In [1]: load( './path/to/file.js' )
loadWorkspace( name[, options] )
Loads variables from a specified workspace into the current workspace.
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
In [3]: workspace( 'barfoo' );
In [4]: typeof x
Out[4]: 'undefined'
In [5]: loadWorkspace( 'foobar' );
In [6]: x
Out[6]: 3.14
The function supports the following options
:
- include: variable name inclusion filter. May be either an array-like
object
or a regular expression. - exclude: variable name exclusion filter. May be either an array-like
object
or a regular expression. - override:
boolean
indicating whether to override existing workspace variables. Default:true
.
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14, y = 6.28;
In [3]: workspace( 'barfoo' );
In [4]: typeof x
Out[4]: 'undefined'
In [5]: loadWorkspace( 'foobar', { 'include': /^x/ } );
In [6]: x
Out[6]: 3.14
In [7]: typeof y
Out[7]: 'undefined'
logStart( fpath )
Starts logging commands and printed output to a specified file path.
// TODO
logStop( id )
Stops logging commands and printed output to a file path associated with a specified record identifier.
// TODO
presentationStart( [text, ][options] )
Starts a REPL presentation.
In [1]: var id = presentationStart( 'beep\n---\nboop\n' );
The function accepts the following options
:
- borderTop: top border character sequence. Default:
'*'
. - borderBottom: bottom border character sequence. Default:
'*'
. - borderLeft: left border character sequence. Default:
'* '
. - borderRight: right border character sequence. Default:
' *'
. - counter: slide counter. Can either be
true
,false
, or'progress'
. Default:false
. - width: presentation width. If
null
, the presentation width is either computed based on the screen size (if a REPL output stream is TTY) or set to80
characters. Default:null
. - height: presentation height. If
null
, the presentation height is either computed based on the screen size (if a REPL output stream is TTY) or set to25
rows. Default:null
. - workspace: REPL workspace name. A presentation adds commands to the specified workspace, thus allowing presentation navigation and interaction. Default:
'presentation-<n>'
, wheren
is an assigned presentation identifier. - load: file path specifying a presentation file to load. If presentation
text
is provided, this option is ignored. Otherwise, this option is required. - watch:
boolean
indicating whether to watch a presentation source file for changes. This option is only applicable if not provided presentationtext
and theoptions
object specifies a presentation file to load. Default:false
. - autoClear:
boolean
indicating whether to automatically clear the screen before writing a rendered slide to the REPL. Default:true
. - loop:
boolean
indicating whether to "loop" a presentation. Default:false
.
A few notes:
- When not provided presentation
text
, an options argument must specify a presentation file to load. - If a specified workspace already exists, the workspace is silently cleared and a new presentation bound. In order to preserve an existing workspace, specify an alternative presentation workspace name.
presentationStop( [id] )
Stops a REPL presentation.
In [1]: var id = presentationStart( 'beep\n---\nboop\n' );
In [2]: presentationStop();
A few notes:
- If provided a presentation identifier, the corresponding presentation is stopped. Otherwise, assuming the function is invoked in a presentation workspace, the current presentation is stopped.
- When stopping a REPL presentation, the presentation's REPL workspace is both cleared and deleted.
quit()
Exits the REPL.
In [1]: quit()
renameTheme( oldName, newName )
Renames a syntax highlighting color theme.
// Add a color theme:
In [1]: addTheme( 'myTheme', { 'keyword': 'red' } )
// Check list of themes:
In [2]: themes()
Out[2]: [ 'stdlib-ansi-basic', 'myTheme' ]
// Rename the added theme:
In [3]: getTheme( 'myTheme', 'yourTheme' )
// Check updated list of themes:
In [4]: themes()
Out[4]: [ 'stdlib-ansi-basic', 'yourTheme' ]
renameWorkspace( oldName, newName )
Renames a workspace.
// Create a new workspace:
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
// List current workspaces:
In [3]: workspaces()
Out[3]: [ 'base', 'foobar' ]
// Switch to another workspace:
In [4]: workspace( 'barfoo' );
// List current workspaces:
In [5]: workspaces()
Out[5]: [ 'base', 'foobar', 'barfoo' ]
// Rename the first workspace:
In [6]: renameWorkspace( 'foobar', 'beepboop' );
// Check the updated list of workspaces:
In [7]: workspaces()
Out[7]: [ 'base', 'barfoo', 'beepboop' ]
// Switch to the renamed workspace:
In [8]: workspace( 'beepboop' );
// Confirm that workspace contains previously defined variables:
In [9]: x
Out[9]: 3.14
Note: the new workspace name must not already exist. The only exception is when the old name and the new name are the same; in which case, invoking this command is a non-operation.
Note: as a 'base'
workspace must always exist, when renaming the 'base'
workspace, variables from the 'base'
workspace are simply copied to a new workspace and the 'base'
workspace cleared of user-defined variables.
require( id )
Imports a module, JSON, or local file.
In [1]: var crypto = require( 'crypto' );
Modules can be imported from node_modules
. Local modules and JSON files can be imported using a relative path (e.g., './foo.js'
, './../bar.json'
, etc) that will be resolved against the current working directory.
rerequire( id )
Re-imports a module, JSON, or local file.
In [1]: var foo = require( './foo.js' );
// Modify `./foo.js`...
// Re-import the module:
In [2]: foo = rerequire( './foo.js' );
Modules can be imported from node_modules
. Local modules and JSON files can be imported using a relative path (e.g., './foo.js'
, './../bar.json'
, etc) that will be resolved against the current working directory.
rerun( [arg] )
Reruns previous commands.
In [1]: 1+1
Out[1]: 2
In [2]: rerun()
By default, the command re-executes the previous command. If provided an integer
, the previous n
commands are re-executed.
In [1]: 1+1
Out[1]: 2
In [2]: 2+2
Out[2]: 4
In [3]: rerun( 2 )
If provided a regular expression, the most recent command matching the regular expression is rerun.
In [1]: var x = base.sin( 3.14 );
In [2]: 1+1
Out[2]: 2
In [3]: rerun( /base\.sin/ )
If provided an array
of command identifiers, the command corresponding to each identifier is rerun.
In [1]: 1+1
Out[1]: 2
In [2]: 2+2
Out[2]: 4
In [3]: 3+3
Out[3]: 6
In [4]: rerun( [ 1, 3 ] )
If provided a subsequence string
, the command corresponding to each resolved command identifier is rerun.
In [1]: 1+1
Out[1]: 2
In [2]: 2+2
Out[2]: 4
In [3]: 3+3
Out[3]: 6
In [4]: rerun( '1:3:2' )
WARNING: be careful when re-evaluating previously executed rerun
commands, as this can lead to infinite execution loops.
reset()
Resets the REPL.
In [1]: reset()
save( fpath )
Saves previous commands to a specified file path.
// TODO
saveStart( fpath )
Starts saving commands to a specified file path.
// TODO
saveStop( id )
Stops saving commands to a file path associated with a specified record identifier.
// TODO
settings( [name[, value]] )
Displays REPL settings.
In [1]: settings()
To retrieve the current value for a specific setting, provide a name
argument.
In [1]: settings( 'autoClosePairs' )
To update a specific setting, provide a value
argument.
In [1]: settings( 'autoClosePairs', false )
themes()
Returns a list of all available syntax highlighting color themes.
// Add a color theme:
In [1]: addTheme( 'myTheme', { 'keyword': 'red' } )
// Check list of themes:
In [2]: themes()
Out[2]: [ 'stdlib-ansi-basic', 'myTheme' ]
tutorial( [name, [options]] )
Starts a tutorial.
In [1]: var id = tutorial( 'repl' );
The function accepts the following options
:
- borderTop: top border character sequence. Default:
'*'
. - borderBottom: bottom border character sequence. Default:
'*'
. - borderLeft: left border character sequence. Default:
'* '
. - borderRight: right border character sequence. Default:
' *'
. - counter: slide counter. Can either be
true
,false
, or'progress'
. Default:progress
. - workspace: REPL workspace name. A tutorial presentation adds commands to the specified workspace, thus allowing tutorial navigation and interaction. Default:
'tutorial-<name>-<n>'
, wherename
is the tutorialname
andn
is an assigned tutorial presentation identifier. - autoClear:
boolean
indicating whether to automatically clear the screen before writing a rendered tutorial slide to the REPL. Default:true
.
A few notes:
- When not provided a tutorial
name
, the function prints a list of available tutorials. - If a specified workspace already exists, the workspace is silently cleared and a new tutorial presentation bound. In order to preserve an existing workspace, specify an alternative tutorial workspace name.
userDoc( alias, [ref,] doc )
Adds user-defined documentation.
In [1]: function foo() {};
In [2]: userDoc( 'foo', foo, '\nfoo()\n Foo bar.\n' );
In [3]: help( foo )
If user-defined documentation already exists for the provided alias, the current documentation is overwritten.
In [1]: function foo() {};
In [2]: userDoc( 'foo', foo, '\nfoo()\n Foo bar.\n' );
In [3]: help( foo )
foo()
Foo bar.
In [4]: userDoc( 'foo', foo, '\nfoo()\n Beep boop.\n' );
In [5]: help( foo )
foo()
Beep boop.
vars( [options] )
Returns a list of variable names in the current workspace.
In [1]: var x = 3.14;
In [2]: vars()
Out[2]: [ 'x' ]
The function supports the following options
:
- include: regular expression variable name inclusion filter.
- exclude: regular expression variable name exclusion filter.
- types: array-like
object
containing variable type inclusion filter(s). - details:
boolean
indicating whether to include additional variable details, such as variable type, contents, etc. Default:false
.
In [1]: var x = 3.14;
In [2]: vars( { 'details': true } )
varsWorkspace( [name, ][options] )
Returns a list of variable names in a specified workspace.
In [1]: var x = 3.14;
// List variable names in the current workspace:
In [2]: varsWorkspace()
Out[2]: [ 'x' ]
In [3]: workspace( 'foo' );
In [4]: varsWorkspace( 'base' )
Out[4]: [ 'x' ]
The function supports the following options
:
- include: regular expression variable name inclusion filter.
- exclude: regular expression variable name exclusion filter.
- types: array-like
object
containing variable type inclusion filter(s). - details:
boolean
indicating whether to include additional variable details, such as variable type, contents, etc. Default:false
.
In [1]: var x = 3.14;
In [2]: workspace( 'foo' );
In [3]: varsWorkspace( 'base', { 'details': true } )
workspace( name )
Switches to a specified workspace.
In [1]: workspace( 'foobar' );
In [2]: var x = 3.14;
In [3]: workspace( 'beepboop' );
In [4]: x
Error: x is not defined
In [5]: workspace( 'foobar' );
In [6]: x
Out[6]: 3.14
If a workspace with the specified name
does not exist, the workspace is created.
workspaces( [options] )
Returns a list of workspace names.
In [1]: workspaces()
Out[1]: [ 'base' ]
The function supports the following options
:
- include: regular expression workspace name inclusion filter.
- exclude: regular expression workspace name exclusion filter.
- details:
boolean
indicating whether to include additional workspace details, such as variable names, types, contents, etc. Default:false
.
In [1]: workspaces( { 'details': true } )
Examples
var join = require( 'path' ).join;
var REPL = require( '@stdlib/repl' );
function onExit() {
console.log( '' );
console.log( 'REPL closed.' );
}
// Create a new REPL:
var repl = new REPL();
repl.on( 'exit', onExit );
// Load a history file:
repl.load( join( __dirname, 'examples', 'history.txt' ), done );
function done() {
// Close the REPL:
repl.close();
}
CLI
Usage
Usage: stdlib-repl [options]
Options:
-h, --help Print this message.
-V, --version Print the package version.
--welcome <message> Welcome message.
--input-prompt <prompt> Input prompt. Default: 'In [%d]: '.
--output-prompt <prompt> Output prompt. Default: 'Out[%d]: '.
--padding <padding> Empty lines between commands. Default: 1.
--load <filepath> JavaScript file to evaluate line-by-line.
--save <filepath> File to save REPL command history.
--logfile <filepath> File to log REPL commands and printed output.
--timeout <timeout> Milliseconds before terminating a command.
--quiet Disable printing of REPL logs and diagnostics.
Examples
$ stdlib-repl