Hello world/Newline omission: Difference between revisions

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 =={{header|J}}==
+With ''jconsole'', <code>stdout</code> can be used.
-On a linux system, you can use 1!:3 because stdout is a file:
-<syntaxhighlight lang="j">   'Goodbye, World!' 1!:3 <'/proc/self/fd/1'
+<syntaxhighlight lang="j">   stdout
-Goodbye, World!   </syntaxhighlight>
+!:2&4</syntaxhighlight>
+<code>1!:2&4</code> returns its input unmodified. To avoid implicit output (which would repeat the output), when used interactively:
-However, J works in environments other than Linux, so...
+<syntaxhighlight lang="j">   put=: 0 0 $ 1!:2&4
+   put 'Goodbye, World!'
+Goodbye, World!</syntaxhighlight>
+However, J also works in graphical environments, which might not be connected to standard output.
 '''Solution''':<code>prompt</code> from the misc package.
 '''Example''':<syntaxhighlight lang="j">   load 'general/misc/prompt'
    prompt 'Goodbye, World!'
 Goodbye, World!</syntaxhighlight>
-'''Notes''':  J programs are normally run from a REPL, or session manager, which comes in several flavors.  The traditional commandline-based terminal (jconsole), one of several desktop applications (jqt for the current version of J, jgtk and jwd for older but still supported versions), a web-based frontend (jhs), and various mobile apps (J for iOS, Android).
+'''Notes''': J programs are normally run from a REPL, or session manager, which comes in several flavors. The traditional commandline-based terminal (jconsole), one of several desktop applications (jqt for the current version of J, jgtk and jwd for older versions), a web-based frontend (jhs), and various mobile apps (J for iOS, Android).
-The specific session manager being used changes the context and therefore answer to this task.  For example, when using J from a browser (including mobile browsers) newlines are omitted by default.  Further, J provides strong tools for coalescing results and manipulating them prior to output, so newline elimination would typically happen before output rather than after.
+The specific session manager being used changes the context and therefore answer to this task. For example, when using J from a browser (including mobile browsers) newlines are omitted by default. Further, J provides strong tools for coalescing results and manipulating them prior to output, so newline elimination would typically happen before output rather than after.
 With that said, <code>prompt</code> handles the most common cases (using binary output for jconsole, so no newline is appended; adjusting the REPL prompt in the desktop apps to to elide the newline which is normally included by default, etc).
-For truly automated processes, you'd almost always want this kind of functionality (omitting the newline when printing) in a file- or stream-oriented application.  For those cases, the simple <code>text 1!:3 file</code> will append the text to the referenced file verbatim, without inserting any extra newlines.
+For truly automated processes, you'd almost always want this kind of functionality (omitting the newline when printing) in a file- or stream-oriented application. For those cases, the simple <code>text 1!:3 file</code> will append the text to the referenced file verbatim, without inserting any extra newlines.
 So, if a J programmer were asked to solve this task, the right approach would be to ask why that is needed, and then craft a solution appropriate to that situation.