[#base_blob-09-2constructor-00]
= xref:base_blob-09.adoc[base&lowbar;blob]::base&lowbar;blob
:relfileprefix: ../
:mrdocs:

Constructors

== Synopses

Declared in `&lt;uint256&period;h&gt;`

Constructs a zero&hyphen;valued blob&period;


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
xref:base_blob-09/2constructor-03.adoc[base&lowbar;blob]();
----

[.small]#xref:base_blob-09/2constructor-03.adoc[_» more&period;&period;&period;_]#

Constructs a blob at compile time from a hex string&period;


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
consteval
explicit
xref:base_blob-09/2constructor-0e.adoc[base&lowbar;blob](std::string&lowbar;view hex&lowbar;str);
----

[.small]#xref:base_blob-09/2constructor-0e.adoc[_» more&period;&period;&period;_]#

Constructs a blob from a single byte constant between 1 and 255&period;


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
explicit
xref:base_blob-09/2constructor-02.adoc[base&lowbar;blob](uint8&lowbar;t v);
----

[.small]#xref:base_blob-09/2constructor-02.adoc[_» more&period;&period;&period;_]#

Constructs a blob by copying bytes from a span&period;


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
explicit
xref:base_blob-09/2constructor-09.adoc[base&lowbar;blob](std::span&lt;unsigned char const&gt; vch);
----

[.small]#xref:base_blob-09/2constructor-09.adoc[_» more&period;&period;&period;_]#

== Parameters

[cols="1,4"]
|===
| Name| Description
| *hex&lowbar;str*
| A hex string that must fit the blob exactly&period;
| *v*
| The byte value placed in the first position of the blob&period;
| *vch*
| A span of exactly WIDTH bytes to copy into the blob&period;
|===


[.small]#Created with https://www.mrdocs.com[MrDocs]#
