Functions and Statements which will spread the tainted mark of a tainted string

Function/Statement	Since
= (assign)	0.1.0
. (concat)	0.1.0
"{$var}" (variable substitution)	0.1.0
.= (assign concat)	0.1.0
strval	0.3.0
explode	0.3.0
implode	0.3.0
sprintf	0.3.0
vsprintf	0.3.0
trim	0.4.0
rtrim	0.4.0
ltrim	0.4.0