ECHO: "Children empty: begin"
ECHO: "child1"
ECHO: "child2"
ECHO: "child3"
ECHO: "child4"
ECHO: "child5"
ECHO: "Children empty: end"
ECHO: "Children scalar: begin"
ECHO: "child1"
ECHO: "child5"
ECHO: "child3"
WARNING: Children index (5) out of bounds (5 children)
WARNING: Negative children index (-1) not allowed
ECHO: "Children scalar: end"
ECHO: "Children vector: begin"
ECHO: "child5"
ECHO: "child1"
ECHO: "child4"
ECHO: "child2"
WARNING: Children index (5) out of bounds (5 children)
WARNING: Negative children index (-1) not allowed
ECHO: "Children vector: end"
ECHO: "Children range: begin"
ECHO: "child1"
ECHO: "child2"
ECHO: "child3"
ECHO: "child4"
ECHO: "child5"
ECHO: "child2"
ECHO: "child3"
ECHO: "child1"
ECHO: "child3"
ECHO: "child5"
ECHO: "Children range: end"