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Programming-Idioms

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Idiom #167 Trim prefix

Create the string t consisting of the string s with its prefix p removed (if s starts with p).

let t = s.trim_start_matches(p);

Warning: this would remove several leading occurrences of p, if present.
See strip_prefix to remove only one occurrence.
let t = s.strip_prefix(p).unwrap_or(s);

Removes p at most once.
let t = if s.starts_with(p) { &s[p.len()..] } else { s };
import std.string;
string t = s.chompPrefix(p);
#include <string.h>
size_t l = strlen(p);
const char * t = strncmp(s, p, l) ? s : s + l;

strlen computes the prefix length and strncmp returns zero if the first l characters match
uses StrUtils;
if AnsiStartsStr(p, s) then 
  t := copy(s, length(p)+1, length(s)-length(p))
else
  s := t;
#include <string>
std::string t = s.starts_with(p) ? s.substr(p.size()) : s;

New implementation...