[#boost-urls-grammar-lut_chars-2constructor-074]
= xref:boost.adoc[boost]::xref:boost/urls.adoc[urls]::xref:boost/urls/grammar.adoc[grammar]::xref:boost/urls/grammar/lut_chars.adoc[lut_chars]::lut_chars
:relfileprefix: ../../../../
:mrdocs:


Constructor

== Synopsis


Declared in `<https://www.github.com/boostorg/url/blob/develop/include/boost/url/grammar/lut_chars.hpp#L188[boost/url/grammar/lut_chars.hpp]>`

[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
lut_chars(char const* s) noexcept;
----

== Description


This function constructs a character        set which has as members, all of the        characters present in the null‐terminated        string `s`.


=== Example

[,cpp]
----
constexpr lut_chars digits = "0123456789";
----

=== Complexity

Linear in `::strlen(s)`, or constant        if `s` is a constant expression.


=== Exception Safety

Throws nothing.



== Parameters


|===
| Name | Description

| *s*
| A null‐terminated string.


|===



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