Translation – INPUT command (Revised)

Now with the updated syntax to the INPUT statement with the addition of the optional PROMPT keyword, the translation needs to be revised. Since the PROMPT keyword will always follow the INPUT keyword, it will be easiest to handle it as the double keyword command INPUT PROMPT, in other words, it will be a separate command. The translations of these two statements will now be:

InputGet {<variable> InputType}... Input
<expr> InputPromptStr {<variable> InputType}... InputPrompt

This mirrors other commands where the command token is placed at the end of the translation. The InputGet code does not need any sub-codes as it will always output “? ” before getting input. The InputPromptStr will have a Question sub-code to determine if an “? ” should be output after the prompt string.

There will also be an InputPromptTmp code for when the prompt string expression is a temporary string, but this determination won't occur until the Encoder can determine if the string is temporary or not. This also mirrors how temporary strings are handled for other codes. If the Tmp sub-code flag was used, this would be a different scheme and would complicate the Encoder implementation of temporary strings. There is a way to avoid the Input or InputPrompt code needing a Tmp sub-code flag (these are where during run-time that a temporary prompt string is will be deleted).

Both the Input and InputPrompt codes will still have the Keep sub-code for when the cursor should not be advanced to the next line. Here are the revised examples originally shown here with their new translations:

INPUT A InputGet A<ref> InputDbl Input
INPUT PROMPT "Qty: ",A% "Qty: " InputPromptStr A% InputInt InputPrompt
INPUT PROMPT P$+C$,A$; P$ C$ +$ InputPromptTmp A$ InputStr InputPrompt'Keep'
INPUT PROMPT "",A,B% "" InputPromptStr A<ref> InputDbl B%<ref> InputInt InputPrompt

Note there is no equivalent to the last INPUT example command that disabled the prompt – the INPUT PROMPT will have to be used with an empty string as shown above. This should not be an issue since prompt-less INPUT statements will not be common. Also notice that there are three codes that will be outputting a prompt and getting the input. Next, how execution is affected by these changes...