# Learning tkz-euclide and getting strange errors

I am using mikTeX on windows, and want to make figures of some compass and ruler constructions. So I want to use tkz-euclide. A minimal working example is the following:

\documentclass{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[usenames,dvipsnames]{xcolor}
\usepackage{lmodern}
\usepackage{tkz-euclide,tkz-fct}
\usetkzobj{all}  \usetikzlibrary{calc,shapes,decorations}

\begin{document}
\begin{tikzpicture}[scale=1.0]
\tkzDefPoint(0,0){C}
\tkzDefPoint(4,5){A}
\tkzDefPoint(4,-1){B}
\tkzDrawArc[R,ultra thin,blue!50](B,3cm)(60,120)
\tkzDrawArc[R,ultra thin,blue!50](A,3cm)(240,300)
\tkzDefMidPoint(A,B) \tkzGetPoint{P}
\tkzDrawPoint[size=5]{P}
% og nå tegne normalen fra P:
\tkzLabelPoints(A,B,C,P)
\tkzDefLine[perpendicular=through P](C,P) \tkzGetPoint{F}
\tkzShowLine[perpendicular=through P,size=2,orange,gap=3](C,P)
\end{tikzpicture}
\end{document}


Running this (using emacs and auctex) gives:

ERROR: Package pgfkeys Error: I do not know the key '/drawpoint/B' and I am going to ignore it. Perhaps you misspelled it.

--- TeX said ---
--- HELP ---
No help available


Since the manual is in french I am a little handicapped ...

• Subtle, but you need (P) after DrawPoint and not {P}... And make the dot bigger if you want to be able to see it. Try \tkzDrawPoint[size=20](P) – Thruston Dec 8 '15 at 22:40

The error seems to come from the argument of \tkzDrawPoint, which should not be between {}but between (). With this modification, the code compiles. I deleted the option usenames for xcolor, as it is obsolete:

\documentclass{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[dvipsnames]{xcolor}
\usepackage{lmodern}
\usepackage{tkz-euclide,tkz-fct}
\usetkzobj{all} \usetikzlibrary{calc,shapes,decorations}

\begin{document}

\begin{tikzpicture}[scale=1.0]
\tkzDefPoint(0,0){C}
\tkzDefPoint(4,5){A}
\tkzDefPoint(4,-1){B}
\tkzDrawArc[R,ultra thin,blue!50](B,3cm)(60,120)
\tkzDrawArc[R,ultra thin,blue!50](A,3cm)(240,300)
\tkzDefMidPoint(A,B) \tkzGetPoint{P}