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This is available as Str\starts_with_l in the www repository.

Returns whether the string starts with the given prefix

namespace HH\Lib\Str;

function starts_with_l(
  \HH\Lib\Locale\Locale $locale,
  string $string,
  string $prefix,
): bool;

Strings will be normalized for comparison in encodings that support multiple representations, such as UTF-8.

For a case-insensitive check, see Str\starts_with_ci_l(). For a byte-wise check, see Str\starts_with()


  • \HH\Lib\Locale\Locale $locale
  • string $string
  • string $prefix


  • bool