Editing JOSS (section)

===Direct and indirect mode===
JOSS introduced the idea of a single [[command line]] editor that worked both as an interactive language and a program editor. Commands that were typed without a line number were executed immediately, in what JOSS referred to as "[[direct mode]]". If the same line was prefixed with a line number, it was instead copied into the program code storage area, which JOSS called "indirect mode". New lines were added to the program if the line number was unique, replaced extant lines with the same number, or removed from the program if an extant line number was typed in with no code following it.{{sfn|Gimble|1967|p=v}}

In contrast to most BASICs, JOSS saved the entire user input to files, not just the program code. When loaded, JOSS essentially typed the lines back in. This meant that ''program files'' could contain both program statements and direct mode instructions. For instance, it was common to see programs that listed the statement lines and then have the file end with {{code|Go.}} to immediately run the program as soon as it completed loading. There were some features that could only be used in direct mode, like {{code|Let}} and {{code|Form}}, which were input without line numbers but still returned when the program was loaded.{{sfn|Gimble|1967|p=vi}}

Direct and indirect instructions could be mixed freely in a workspace. This allowed comments to be inserted in [[source code]] by adding direct-mode lines beginning with {{code|*}},{{sfn|Gimble|1967|p=65}} or by placing one at the end of a line of code and then adding a comment after it. Blank lines were also ignored, allowing the program to be broken up for clarity.{{sfn|Marks|1971|p=42}}