REPL

CommandBox contains a REPL command which is a powerful tool to execute ad-hoc CFML code from the command line. A REPL reads user input, evaluates it, prints the result, and then repeats the process. The CommandBox REPL supports the inline execution of both CF script or tags.

CFSCRIPT-REPL: 5+5
=> 10

Script REPL

The default mode of the REPL command is to accept script. You can enter most any CF Script into the prompt for execution. If the script is an expression that returns a value, or sets a variable, that value/variable will be output. Variables that you set will be available to you until you exit the REPL command.

CFSCRIPT-REPL: breakfast = ['bacon','eggs']
=> [
    "bacon",
    "eggs"
]
CFSCRIPT-REPL: breakfast.len()
=> 2
CFSCRIPT-REPL: breakfast.append( 'orange juice' )
=> [
    "bacon",
    "eggs",
    "orange juice"
]

Multi-line

Multi-line statements are also allowed. If you have typed a starting { without an ending }, the REPL will keep accepting lines until it has determined the statement to be finished. The prompt changes to ... until the statement is finished.

CFSCRIPT-REPL: for( item in breakfast ) {
...echo( item & chr(10) )
...}
=> bacon
eggs
orange juice

If you would like to abort a multi-line statement, simply type exit at the prompt.

Tag REPL

You can also enter tags at the REPL. Switch to this mode by setting the script flag to false.

REPL --!script

Any output from the tags will be returned to the console.

CFML-REPL: plain text
=> plain text
CFML-REPL: <cfset name = "Brad Wood">
=>
CFML-REPL: <cfoutput>#reverse( name )#</cfoutput>
=> dooW darB
CFML-REPL: <cfif 1 eq 2>yes<cfelse>no</cfif>
=> no

Multi-line statements are not currently supported in the tag REPL.

History

The script and tag REPL have their only history. Use the up and down arrows to access previous things you typed. Your REPL history can be viewed and managed by the history command (once you exit the REPL).

history type=scriptrepl
history type=tagrepl --clear

Tab completion is currently not supported in either of the REPLs.

Environment Variable Expansions

You can use environment variable expansions in the REPL with the same syntax that works in the CLI and JSON files. Consider this example which sets an environment variable in the shell and then enters the REPL command and references the variable. Note, the variable is expanded in-place, so you still need to wrap it in quotes so the resulting CFML code is valid.

CommandBox> set foo=bar
CommandBox> REPL

CFSCRIPT-REPL: echo( '${foo}' )
bar

Escapes work the same way in the REPL

CFSCRIPT-REPL: echo( '\${foo}' )
${foo}

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