(1:1)--(-1:2)--(2,2)

documentclass{article}
usepackage{tikz,expl3,xparse}

ExplSyntaxOn

NewDocumentCommand{makelinesegment}{ m } {
    tl_set:Nn l_bob_func_tl { #1 }
    regex_replace_all:nnN { ([0-9])- } { 1)--( } l_bob_func_tl
    regex_replace_all:nnN { : } { , } l_bob_func_tl
    (l_bob_func_tl)
}

ExplSyntaxOff

begin{document}

makelinesegment{1:1--1:2-2:2}

% If uncommented
% Package tikz Error: Giving up on this path. Did you forget a semicolon?.
%tikzdraw makelinesegment{1:1--1:2-2:2} ;

end{document}