The Template:Str_index_code extracts a character from parameter 1, at the location in parameter 2, using an encode/decode method for handling special markup characters. Any character can be extracted, including: colon, semicolon, asterisk ('*') and hashmark ('#').
The Template:str_index_any extracts a specified nth character from a string, even allowing for accented letters or diacritics to be included in the string. The string can be any length, but position n (parameter 2) is limited to 500 at most.
{{str index any|text|n}} = Returns the n-th character of text.
Supports a larger character set, allowing the text to have accented letters or other diacritical marks. Returns an error message for unknown characters. Returns   for a blank space, which can be converted to a simple space by xspace.
{{ Str index code |Very very...long string of 500 characteRs|499}} → R
{{ Str len |{{ Str index code |a b|1}}}} → 1
{{ Str len |{{ Str index code |a b|2}}}} → 34
{{ Str len |{{ Str index code |a b|3}}}} → 1
The last example shows extraction of letter "b" with string length as 1. The prior example extracts a blank but considers the length as 5 for the 5 characters " " even though there is only 1 space, and hence, {{str len| }} → 5. If surrounded by 2 other characters, then the length might be totalled incorrectly as 7 (rather than 3 characters):
{{ Str len |<{{ Str index code |a b|2}}>}} → 36
{{ Str len |X{{ Str index code |a b|2}}X}} → 36
{{ Str len |X{{ Str index |a b|2}}X}} → 3
X{{ Str index code |a b|2}}X → X X
The same string-length problem occurs when using template {{ Str index }}. There might be other quirks as well, but most cases work as expected.
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