Outside $idx: {$idx}{~n}
Outside $len: {$len}{~n}
Outside {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
Outside {?$len}$len is true{:else}$len is false{/$len}{~n}

{#things}
    Inside Section $idx: {$idx}{~n}
    Inside Section $len: {$len}{~n}
    Inside Section {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Inside Section {?$len}$len is true{:else}$len is false{/$len}{~n}
{:else}
    Else Section $idx: {$idx}{~n}
    Else Section $len: {$len}{~n}
    Else Section {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Else Section {?$len}$len is true{:else}$len is false{/$len}{~n}
{/things}

{?things}
    Inside Exists $idx: {$idx}{~n}
    Inside Exists $len: {$len}{~n}
    Inside Exists {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Inside Exists {?$len}$len is true{:else}$len is false{/$len}{~n}
{:else}
    Else Exists $idx: {$idx}{~n}
    Else Exists $len: {$len}{~n}
    Else Exists {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Else Exists {?$len}$len is true{:else}$len is false{/$len}{~n}
{/things}

{^things}
    Inside Not Exists $idx: {$idx}{~n}
    Inside Not Exists $len: {$len}{~n}
    Inside Not Exists {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Inside Not Exists {?$len}$len is true{:else}$len is false{/$len}{~n}
{:else}
    Else Not Exists $idx: {$idx}{~n}
    Else Not Exists $len: {$len}{~n}
    Else Not Exists {?$idx}$idx is true{:else}$idx is false{/$idx}{~n}
    Else Not Exists {?$len}$len is true{:else}$len is false{/$len}{~n}
{/things}