Text editor with autocomplete while typing normal text

Try the builtin dabbrev-expand; it's bound to M-/

pabbrev-mode (predictive abbreviation) works by examining previously written text. Unlike dynamic abbreviation, the text is analyzed during idle time (which enables quick lookup of potential abbreviations). Pabbrev looks at word frequency to suggest the most common expression.

From the documentation, this is what it might look like as you typed the keys pred.


p[oint]
pr
[ogn]
pre
[-command-hook]
pred
[ictive]


HippieExpand looks at the word before point and tries to expand it in various ways including expanding from a fixed list (like `‘expand-abbrev’’), expanding from matching text found in a buffer (like `‘dabbrev-expand’’)
or expanding in ways defined by your own functions. Which of these it
tries and in what order is controlled by a configurable list of
functions.

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