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DeHackEd text string length limitations

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As we know in DeHackEd a text replacement is limited by the original, in chunks of 4 characters (0-3, 4-7, 8-11, 12-15, and so on). The DeHackEd documantation says:

Because each text string is a fixed length in the Doom exe file, you have only a slight lee-way in how long the edited text needs to be. The minimum and maximum length for the string you are editing are shown on the top line of the editing window, along with the current position of the character you're on. You will have a range of 4 characters that the new string must fit into. Typing beyond the maximum number of characters is not allowed, and stopping short of the minimum is also not allowed.

Is this because Greg Lewis found it convenient for the format of the patches, or due to potential issues or instability? I mean, strings exceeding the range shouldn't normally be possible because the new text just wouldn't fit, but would shorter ones using null bytes be harmless?

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myk said:

but would shorter ones using null bytes be harmless?

Why not. Greg Lewis prob'ly wanted to stay safe. The source porters know the best, unless DosDoom decided elsewise.

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As with the code pointer limitation it was just wrong. Since strings are 0-terminated they can easily be shorter.

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I see no reason why shorter strings would not work (in a patched EXE), although Greg's parser may require or assume the limits he set, so editing a DEH files by hand may cause it to fail with DeHackEd (ports probably don't have that limitation).

Some DEH files use spaces on the end to work around that limitation.

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