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<?xml version="1.0" encoding="UTF-8"?>
<helpdocument version="1.0">
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<meta>
<topic id="textsbasicshared03100700xml" indexer="include" status="PUBLISH">
<title id="tit" xml-lang="en-US">Const Statement</title>
<filename>/text/sbasic/shared/03100700.xhp</filename>
</topic>
</meta>
<body>
<section id="const">
<bookmark xml-lang="en-US" branch="index" id="bm_id3146958">
<bookmark_value>Const statement</bookmark_value>
</bookmark>
<paragraph id="hd_id3146958" role="heading" level="1" xml-lang="en-US"><link href="text/sbasic/shared/03100700.xhp" name="Const Statement">Const Statement</link></paragraph>
<paragraph id="par_id3154143" role="paragraph" xml-lang="en-US">Defines one or more identifiers as constants.</paragraph>
</section>
<paragraph id="par_id3147264" role="paragraph" xml-lang="en-US">A constant is a variable that helps to improve the readability of a program. Constants are not defined as a specific type of variable, but rather are used as placeholders in the code. You can only define a constant once and it cannot be modified.</paragraph>
<embed href="text/sbasic/shared/00000003.xhp#functsyntax"/>
<paragraph role="image" id="par_id831588865616326">
<image src="media/helpimg/sbasic/Const_statement.svg" id="img_id651588865616326"><alt id="alt_id281588865616326">Const syntax</alt></image>
</paragraph>
<bascode>
<paragraph id="par_id3150984" role="bascode" xml-lang="en-US">[Global|Private|Public] Const name = expression[, ...]</paragraph>
</bascode>
<embed href="text/sbasic/shared/00000003.xhp#functparameters"/>
<paragraph id="par_id3153897" role="paragraph"> <emph>name:</emph> Any identifier that follows the standard variable naming conventions.</paragraph>
<paragraph role="paragraph" id="par_id791593689338208"><emph>expression:</emph> Any literal expression. </paragraph>
<paragraph id="par_id3150400" role="paragraph" xml-lang="en-US">The data type must be omitted. When a library gets loaded in memory, %PRODUCTNAME Basic converts the program code internally so that each time a constant is used, the defined expression replaces it.</paragraph>
<h3 id="hd_id51593690561479">Scope</h3>
<paragraph role="paragraph" id="par_id431593690612961">By default constants are defined as private in modules and routines. Constants can be made public or global in order to be used from all modules, from all Basic libraries.</paragraph>
<paragraph role="paragraph" id="par_id241593693307830"><literal>Global</literal>, <literal>Private</literal> and <literal>Public</literal> specifiers can only be used for module constants.</paragraph>
<embed href="text/sbasic/shared/00000003.xhp#functexample"/>
<bascode>
<paragraph role="bascode" id="bas_id911593692598060" xml-lang="en-US">Const EARTH = "♁" ' module scope</paragraph>
<paragraph role="bascode" id="bas_id441593692601125" xml-lang="en-US">Private Const MOON = "☾" ' module scope</paragraph>
<paragraph role="bascode" id="bas_id161593692601597" xml-lang="en-US">Public Const VENUS="♀", MARS="♂" ' general scope</paragraph>
<paragraph role="bascode" id="bas_id581593692602046" xml-lang="en-US">Global Const SUN = "☉", STAR = "☆" ' general scope</paragraph>
<paragraph role="bascode" id="bas_id711593692602477" localize="false"></paragraph>
<paragraph id="par_idm1341161984" role="bascode" localize="false">Sub ExampleConst</paragraph>
<paragraph id="par_idm1341160752" role="bascode" xml-lang="en-US"> Const SUN = 3 * 1.456 / 56 ' SUN is local</paragraph>
<paragraph id="par_idm1341159520" role="bascode" xml-lang="en-US"> MsgBox SUN,, MOON ' SUN global constant is unchanged</paragraph>
<paragraph id="par_id3153969" role="bascode" localize="false"> Const Pgm = "Program", Var = 1.00</paragraph>
<paragraph id="par_idm1341156544" role="bascode" localize="false"> MsgBox Pgm & " " & Var, , VENUS &" and "& MARS</paragraph>
<paragraph id="par_idm1341155296" role="bascode" localize="false">End Sub</paragraph>
</bascode>
<section id="relatedtopics">
<paragraph role="paragraph" id="par_id111593694878677"><link href="text/sbasic/shared/enum.xhp" name="Enum">Enum</link> statement</paragraph>
<paragraph role="paragraph" id="par_id111953694878677"><link href="text/sbasic/shared/03090413.xhp" name="Enum">Type</link> statement</paragraph>
</section>
</body>
</helpdocument>
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