Unable to instantiate template with same name as function

[Shriramana Sharma via Digitalmars-d-learn]

Hello. I have a function I want to make CTFE-able as a template.

string ta(string s) { return s ~ "1"; }
template ta(string s) { enum ta = ta(s); }
void main() { string s = ta!"s"; }

Compiling the above I get the errors:

<src>(2): Error: forward reference of variable ta
<src>(3): Error: template instance <src>.ta!"s" error instantiating

Please clarify what I am doing wrong? Thanks!

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Shriramana Sharma, Penguin #395953