As a statement, overwrite characters in a string. As a function, return a slice. Positions are 1-based.
MID$(s$, start [, length]) = t$ MID$(s$, start [, length])
s$ - string variable (statement) or string (function) start - first character position (1-based) length - number of characters (optional) t$ - replacement text (statement)
Example:
A$ = "MMXXXX" : MID$(A$, 3, 4) = "BASIC" : PRINT A$
PRINT MID$("MMBASIC", 3, 4)Source: docs/help/mid-dollar.txt inmmcore. On the computer, typeHELP MID$.