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>coerce | Common Lisp Nova Spec</TITLE
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>Apropos </SPAN
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><INPUT ID="apropos" AUTOFOCUS="AUTOFOCUS" PLACEHOLDER="Type here to search" ONINPUT="aproposInput(this);" ONKEYUP="aproposKeyup(event);" ONCHANGE="aproposChange(this);" ONFOCUS="aproposFocus(this);" ONFOCUSOUT="aproposFocusout(this);"
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><DIV CLASS="matter"
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><DIV CLASS="com"
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><DIV CLASS="begincom"
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><HR
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><TABLE WIDTH="100%" CELLSPACING="0" CELLPADDING="0"
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><TR
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><TD ALIGN="LEFT" VALIGN="BASELINE" WIDTH="100%" CLASS="name"
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><SPAN CLASS="idx" DATA-KIND="idxref" DATA-TERM="coerce"
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></SPAN
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><B
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>coerce</B
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></TD
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><TD ALIGN="RIGHT" VALIGN="BASELINE" WIDTH="0" NOWRAP="NOWRAP" CLASS="ftype"
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><I
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>Function</I
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></TD
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></TR
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></TABLE
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><HR
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></DIV
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><UL CLASS="subtoc"
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></UL
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><DL
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><DT
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><B
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>Syntax</B
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></DT
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><DD
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><P CLASS="j"
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><B
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>coerce</B
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> <SPAN CLASS="cmssi"
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>object</SPAN
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> <SPAN CLASS="cmssi"
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>result-type</SPAN
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> <SPAN CLASS="arrow"
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>→</SPAN
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> <SPAN CLASS="cmssi"
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>result</SPAN
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></P
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></DD
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><DT
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><B
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>Arguments and Values</B
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></DT
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><DD
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><P CLASS="j"
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><VAR CLASS="param"
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>object</VAR
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> — an <A HREF="26_1_Glossary.html#object"
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><EM CLASS="term"
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>object</EM
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></A
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>. </P
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><P CLASS="j"
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><VAR CLASS="param"
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>result-type</VAR
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> — a <A HREF="26_1_Glossary.html#type_specifier"
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><EM CLASS="term"
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>type specifier</EM
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></A
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>. </P
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><P CLASS="j"
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><VAR CLASS="param"
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>result</VAR
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> — an <A HREF="26_1_Glossary.html#object"
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><EM CLASS="term"
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>object</EM
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></A
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>, of <A HREF="26_1_Glossary.html#type"
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><EM CLASS="term"
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>type</EM
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></A
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> <VAR CLASS="param"
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>result-type</VAR
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> except in situations described in <A HREF="12_1_Number_Concepts.html#sec_12_1_5_3" CLASS="secref"
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><SPAN CLASS="cmr"
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>Section</SPAN
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> <SPAN CLASS="cmr"
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>12.1.5.3</SPAN
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> <SPAN CLASS="cmr"
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>(Rule</SPAN
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> <SPAN CLASS="cmr"
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>of</SPAN
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> <SPAN CLASS="cmr"
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>Canonical</SPAN
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> <SPAN CLASS="cmr"
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>Representation</SPAN
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> <SPAN CLASS="cmr"
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>for</SPAN
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> <SPAN CLASS="cmr"
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>Complex</SPAN
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> <SPAN CLASS="cmr"
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>Rationals)</SPAN
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></A
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>.</P
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></DD
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><DT
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><B
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>Description</B
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></DT
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><DD
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><P CLASS="j"
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><A HREF="26_1_Glossary.html#coerce"
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><EM CLASS="term"
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>Coerces</EM
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></A
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> the <VAR CLASS="param"
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>object</VAR
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> to <A HREF="26_1_Glossary.html#type"
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><EM CLASS="term"
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>type</EM
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></A
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> <VAR CLASS="param"
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>result-type</VAR
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>. </P
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><P CLASS="j"
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>If <VAR CLASS="param"
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>object</VAR
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> is already of <A HREF="26_1_Glossary.html#type"
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><EM CLASS="term"
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>type</EM
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></A
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> <VAR CLASS="param"
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>result-type</VAR
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>, the <VAR CLASS="param"
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>object</VAR
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> itself is returned, regardless of whether it would have been possible in general to coerce an <A HREF="26_1_Glossary.html#object"
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><EM CLASS="term"
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>object</EM
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></A
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> of some other <A HREF="26_1_Glossary.html#type"
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><EM CLASS="term"
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>type</EM
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></A
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> to <VAR CLASS="param"
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>result-type</VAR
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>. </P
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><P CLASS="j"
|
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>Otherwise, the <VAR CLASS="param"
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>object</VAR
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> is <A HREF="26_1_Glossary.html#coerce"
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><EM CLASS="term"
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>coerced</EM
|
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></A
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> to <A HREF="26_1_Glossary.html#type"
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><EM CLASS="term"
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>type</EM
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></A
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> <VAR CLASS="param"
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>result-type</VAR
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> according to the following rules:</P
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><DL
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><DT
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><A HREF="t_sequence.html" CLASS="typeref"
|
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><B
|
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>sequence</B
|
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></A
|
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></DT
|
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><DD
|
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><P CLASS="j"
|
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>If the <VAR CLASS="param"
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>result-type</VAR
|
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> is a <A HREF="26_1_Glossary.html#recognizable_subtype"
|
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><EM CLASS="term"
|
|
>recognizable subtype</EM
|
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></A
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> of <A HREF="t_list.html" CLASS="typeref"
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|
><B
|
|
>list</B
|
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></A
|
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>, and the <A HREF="26_1_Glossary.html#object"
|
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><EM CLASS="term"
|
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>object</EM
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></A
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> is a <A HREF="26_1_Glossary.html#sequence"
|
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><EM CLASS="term"
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>sequence</EM
|
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></A
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>, then the <VAR CLASS="param"
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>result</VAR
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> is a <A HREF="26_1_Glossary.html#list"
|
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><EM CLASS="term"
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>list</EM
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></A
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> that has the <A HREF="26_1_Glossary.html#same"
|
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><EM CLASS="term"
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>same</EM
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></A
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> <A HREF="26_1_Glossary.html#element"
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><EM CLASS="term"
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>elements</EM
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></A
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> as <VAR CLASS="param"
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>object</VAR
|
|
>. </P
|
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><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
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>result-type</VAR
|
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> is a <A HREF="26_1_Glossary.html#recognizable_subtype"
|
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><EM CLASS="term"
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>recognizable subtype</EM
|
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></A
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> of <A HREF="t_vector.html" CLASS="typeref"
|
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><B
|
|
>vector</B
|
|
></A
|
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>, and the <A HREF="26_1_Glossary.html#object"
|
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><EM CLASS="term"
|
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>object</EM
|
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></A
|
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> is a <A HREF="26_1_Glossary.html#sequence"
|
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><EM CLASS="term"
|
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>sequence</EM
|
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></A
|
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>, then the <VAR CLASS="param"
|
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>result</VAR
|
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> is a <A HREF="26_1_Glossary.html#vector"
|
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><EM CLASS="term"
|
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>vector</EM
|
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></A
|
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> that has the <A HREF="26_1_Glossary.html#same"
|
|
><EM CLASS="term"
|
|
>same</EM
|
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></A
|
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> <A HREF="26_1_Glossary.html#element"
|
|
><EM CLASS="term"
|
|
>elements</EM
|
|
></A
|
|
> as <VAR CLASS="param"
|
|
>object</VAR
|
|
>. If <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is a specialized <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
>, the <VAR CLASS="param"
|
|
>result</VAR
|
|
> has an <A HREF="26_1_Glossary.html#actual_array_element_type"
|
|
><EM CLASS="term"
|
|
>actual array element type</EM
|
|
></A
|
|
> that is the result of <A HREF="26_1_Glossary.html#upgrade"
|
|
><EM CLASS="term"
|
|
>upgrading</EM
|
|
></A
|
|
> the element type part of that <A HREF="26_1_Glossary.html#specialized"
|
|
><EM CLASS="term"
|
|
>specialized</EM
|
|
></A
|
|
> <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
>. If no element type is specified, the element type defaults to <A HREF="t_t.html" CLASS="typeref"
|
|
><B
|
|
>t</B
|
|
></A
|
|
>. If the <A HREF="26_1_Glossary.html#implementation"
|
|
><EM CLASS="term"
|
|
>implementation</EM
|
|
></A
|
|
> cannot determine the element type, an error is signaled.</P
|
|
></DD
|
|
><DT
|
|
><A HREF="t_character.html" CLASS="typeref"
|
|
><B
|
|
>character</B
|
|
></A
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_character.html" CLASS="typeref"
|
|
><B
|
|
>character</B
|
|
></A
|
|
> and the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> is a <A HREF="26_1_Glossary.html#character_designator"
|
|
><EM CLASS="term"
|
|
>character designator</EM
|
|
></A
|
|
>, the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is the <A HREF="26_1_Glossary.html#character"
|
|
><EM CLASS="term"
|
|
>character</EM
|
|
></A
|
|
> it denotes.</P
|
|
></DD
|
|
><DT
|
|
><A HREF="t_complex.html" CLASS="typeref"
|
|
><B
|
|
>complex</B
|
|
></A
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_complex.html" CLASS="typeref"
|
|
><B
|
|
>complex</B
|
|
></A
|
|
> and the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> is a <EM CLASS="term"
|
|
>real</EM
|
|
>, then the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is obtained by constructing a <A HREF="26_1_Glossary.html#complex"
|
|
><EM CLASS="term"
|
|
>complex</EM
|
|
></A
|
|
> whose real part is the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> and whose imaginary part is the result of <A HREF="26_1_Glossary.html#coerce"
|
|
><EM CLASS="term"
|
|
>coercing</EM
|
|
></A
|
|
> an <A HREF="26_1_Glossary.html#integer"
|
|
><EM CLASS="term"
|
|
>integer</EM
|
|
></A
|
|
> zero to the <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> of the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> (using <A HREF="f_coerce.html" CLASS="funref"
|
|
><B
|
|
>coerce</B
|
|
></A
|
|
>). (If the real part is a <A HREF="26_1_Glossary.html#rational"
|
|
><EM CLASS="term"
|
|
>rational</EM
|
|
></A
|
|
>, however, then the result must be represented as a <A HREF="26_1_Glossary.html#rational"
|
|
><EM CLASS="term"
|
|
>rational</EM
|
|
></A
|
|
> rather than a <A HREF="26_1_Glossary.html#complex"
|
|
><EM CLASS="term"
|
|
>complex</EM
|
|
></A
|
|
>; see <A HREF="12_1_Number_Concepts.html#sec_12_1_5_3" CLASS="secref"
|
|
><SPAN CLASS="cmr"
|
|
>Section</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>12.1.5.3</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>(Rule</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>of</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>Canonical</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>Representation</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>for</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>Complex</SPAN
|
|
> <SPAN CLASS="cmr"
|
|
>Rationals)</SPAN
|
|
></A
|
|
>. So, for example, <CODE CLASS="f"
|
|
>(coerce 3 'complex)</CODE
|
|
> is permissible, but will return <CODE CLASS="f"
|
|
>3</CODE
|
|
>, which is not a <A HREF="26_1_Glossary.html#complex"
|
|
><EM CLASS="term"
|
|
>complex</EM
|
|
></A
|
|
>.)</P
|
|
></DD
|
|
><DT
|
|
><A HREF="t_float.html" CLASS="typeref"
|
|
><B
|
|
>float</B
|
|
></A
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is any of <A HREF="t_float.html" CLASS="typeref"
|
|
><B
|
|
>float</B
|
|
></A
|
|
>, <A HREF="t_short-float.html" CLASS="typeref"
|
|
><B
|
|
>short-float</B
|
|
></A
|
|
>, <A HREF="t_short-float.html" CLASS="typeref"
|
|
><B
|
|
>single-float</B
|
|
></A
|
|
>, <A HREF="t_short-float.html" CLASS="typeref"
|
|
><B
|
|
>double-float</B
|
|
></A
|
|
>, <A HREF="t_short-float.html" CLASS="typeref"
|
|
><B
|
|
>long-float</B
|
|
></A
|
|
>, and the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> is a <EM CLASS="term"
|
|
>real</EM
|
|
>, then the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is a <A HREF="26_1_Glossary.html#float"
|
|
><EM CLASS="term"
|
|
>float</EM
|
|
></A
|
|
> of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> which is equal in sign and magnitude to the <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> to whatever degree of representational precision is permitted by that <A HREF="26_1_Glossary.html#float"
|
|
><EM CLASS="term"
|
|
>float</EM
|
|
></A
|
|
> representation. (If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_float.html" CLASS="typeref"
|
|
><B
|
|
>float</B
|
|
></A
|
|
> and <VAR CLASS="param"
|
|
>object</VAR
|
|
> is not already a <A HREF="26_1_Glossary.html#float"
|
|
><EM CLASS="term"
|
|
>float</EM
|
|
></A
|
|
>, then the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is a <A HREF="26_1_Glossary.html#single_float"
|
|
><EM CLASS="term"
|
|
>single float</EM
|
|
></A
|
|
>.)</P
|
|
></DD
|
|
><DT
|
|
><A HREF="t_function.html" CLASS="typeref"
|
|
><B
|
|
>function</B
|
|
></A
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_function.html" CLASS="typeref"
|
|
><B
|
|
>function</B
|
|
></A
|
|
>, and <VAR CLASS="param"
|
|
>object</VAR
|
|
> is any <A HREF="26_1_Glossary.html#function_name"
|
|
><EM CLASS="term"
|
|
>function name</EM
|
|
></A
|
|
> that is <A HREF="26_1_Glossary.html#fbound"
|
|
><EM CLASS="term"
|
|
>fbound</EM
|
|
></A
|
|
> but that is globally defined neither as a <A HREF="26_1_Glossary.html#macro_name"
|
|
><EM CLASS="term"
|
|
>macro name</EM
|
|
></A
|
|
> nor as a <A HREF="26_1_Glossary.html#special_operator"
|
|
><EM CLASS="term"
|
|
>special operator</EM
|
|
></A
|
|
>, then the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is the <A HREF="26_1_Glossary.html#functional_value"
|
|
><EM CLASS="term"
|
|
>functional value</EM
|
|
></A
|
|
> of <VAR CLASS="param"
|
|
>object</VAR
|
|
>. </P
|
|
><P CLASS="j"
|
|
>If the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_function.html" CLASS="typeref"
|
|
><B
|
|
>function</B
|
|
></A
|
|
>, and <VAR CLASS="param"
|
|
>object</VAR
|
|
> is a <A HREF="26_1_Glossary.html#lambda_expression"
|
|
><EM CLASS="term"
|
|
>lambda expression</EM
|
|
></A
|
|
>, then the <VAR CLASS="param"
|
|
>result</VAR
|
|
> is a <A HREF="26_1_Glossary.html#closure"
|
|
><EM CLASS="term"
|
|
>closure</EM
|
|
></A
|
|
> of <VAR CLASS="param"
|
|
>object</VAR
|
|
> in the <A HREF="26_1_Glossary.html#null_lexical_environment"
|
|
><EM CLASS="term"
|
|
>null lexical environment</EM
|
|
></A
|
|
>.</P
|
|
></DD
|
|
><DT
|
|
><A HREF="t_t.html" CLASS="typeref"
|
|
><B
|
|
>t</B
|
|
></A
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>Any <VAR CLASS="param"
|
|
>object</VAR
|
|
> can be <A HREF="26_1_Glossary.html#coerce"
|
|
><EM CLASS="term"
|
|
>coerced</EM
|
|
></A
|
|
> to an <A HREF="26_1_Glossary.html#object"
|
|
><EM CLASS="term"
|
|
>object</EM
|
|
></A
|
|
> of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <A HREF="t_t.html" CLASS="typeref"
|
|
><B
|
|
>t</B
|
|
></A
|
|
>. In this case, the <VAR CLASS="param"
|
|
>object</VAR
|
|
> is simply returned.</P
|
|
></DD
|
|
></DL
|
|
></DD
|
|
><DT
|
|
><B
|
|
>Examples</B
|
|
></DT
|
|
><DD
|
|
><PRE CLASS="screen"
|
|
>(coerce '(a b c) 'vector) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> #(A B C)
|
|
(coerce 'a 'character) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> #\A
|
|
(coerce 4.56 'complex) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> #C(4.56 0.0)
|
|
(coerce 4.5s0 'complex) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> #C(4.5s0 0.0s0)
|
|
(coerce 7/2 'complex) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> 7/2
|
|
(coerce 0 'short-float) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> 0.0s0
|
|
(coerce 3.5L0 'float) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> 3.5L0
|
|
(coerce 7/2 'float) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> 3.5
|
|
(coerce (cons 1 2) t) <SPAN CLASS="cmsy"
|
|
><SPAN CLASS="arrow"
|
|
>→</SPAN
|
|
></SPAN
|
|
> (1 . 2)</PRE
|
|
><P CLASS="j"
|
|
>All the following <A HREF="26_1_Glossary.html#form"
|
|
><EM CLASS="term"
|
|
>forms</EM
|
|
></A
|
|
> should signal an error:</P
|
|
><PRE CLASS="screen"
|
|
>(coerce '(a b c) '(vector * 4))
|
|
(coerce #(a b c) '(vector * 4))
|
|
(coerce '(a b c) '(vector * 2))
|
|
(coerce #(a b c) '(vector * 2))
|
|
(coerce "foo" '(string 2))
|
|
(coerce #(#\a #\b #\c) '(string 2))
|
|
(coerce '(0 1) '(simple-bit-vector 3))</PRE
|
|
></DD
|
|
><DT
|
|
><B
|
|
>Exceptional Situations</B
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>If a coercion is not possible, an error of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <A HREF="t_type-error.html" CLASS="typeref"
|
|
><B
|
|
>type-error</B
|
|
></A
|
|
> is signaled. </P
|
|
><P CLASS="j"
|
|
><CODE CLASS="f"
|
|
>(coerce x 'nil)</CODE
|
|
> always signals an error of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <A HREF="t_type-error.html" CLASS="typeref"
|
|
><B
|
|
>type-error</B
|
|
></A
|
|
>. </P
|
|
><P CLASS="j"
|
|
>An error of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <A HREF="t_error.html" CLASS="typeref"
|
|
><B
|
|
>error</B
|
|
></A
|
|
> is signaled if the <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> is <A HREF="t_function.html" CLASS="typeref"
|
|
><B
|
|
>function</B
|
|
></A
|
|
> but <VAR CLASS="param"
|
|
>object</VAR
|
|
> is a <A HREF="26_1_Glossary.html#symbol"
|
|
><EM CLASS="term"
|
|
>symbol</EM
|
|
></A
|
|
> that is not <A HREF="26_1_Glossary.html#fbound"
|
|
><EM CLASS="term"
|
|
>fbound</EM
|
|
></A
|
|
> or if the <A HREF="26_1_Glossary.html#symbol"
|
|
><EM CLASS="term"
|
|
>symbol</EM
|
|
></A
|
|
> names a <A HREF="26_1_Glossary.html#macro"
|
|
><EM CLASS="term"
|
|
>macro</EM
|
|
></A
|
|
> or a <A HREF="26_1_Glossary.html#special_operator"
|
|
><EM CLASS="term"
|
|
>special operator</EM
|
|
></A
|
|
>. </P
|
|
><P CLASS="j"
|
|
>An error of <A HREF="26_1_Glossary.html#type"
|
|
><EM CLASS="term"
|
|
>type</EM
|
|
></A
|
|
> <A HREF="t_type-error.html" CLASS="typeref"
|
|
><B
|
|
>type-error</B
|
|
></A
|
|
> should be signaled if <VAR CLASS="param"
|
|
>result-type</VAR
|
|
> specifies the number of elements and <VAR CLASS="param"
|
|
>object</VAR
|
|
> is of a different length.</P
|
|
></DD
|
|
><DT
|
|
><B
|
|
>See Also</B
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
><A HREF="f_rational.html" CLASS="funref"
|
|
><B
|
|
>rational</B
|
|
></A
|
|
>, <A HREF="f_floor.html" CLASS="funref"
|
|
><B
|
|
>floor</B
|
|
></A
|
|
>, <A HREF="f_char-code.html" CLASS="funref"
|
|
><B
|
|
>char-code</B
|
|
></A
|
|
>, <A HREF="f_char-int.html" CLASS="funref"
|
|
><B
|
|
>char-int</B
|
|
></A
|
|
></P
|
|
></DD
|
|
><DT
|
|
><B
|
|
>Notes</B
|
|
></DT
|
|
><DD
|
|
><P CLASS="j"
|
|
>Coercions from <A HREF="26_1_Glossary.html#float"
|
|
><EM CLASS="term"
|
|
>floats</EM
|
|
></A
|
|
> to <A HREF="26_1_Glossary.html#rational"
|
|
><EM CLASS="term"
|
|
>rationals</EM
|
|
></A
|
|
> and from <A HREF="26_1_Glossary.html#ratio"
|
|
><EM CLASS="term"
|
|
>ratios</EM
|
|
></A
|
|
> to <A HREF="26_1_Glossary.html#integer"
|
|
><EM CLASS="term"
|
|
>integers</EM
|
|
></A
|
|
> are not provided because of rounding problems.</P
|
|
><PRE CLASS="screen"
|
|
>(coerce x 't) <SPAN CLASS="cmsy"
|
|
><SPAN STYLE="font-size:16px;vertical-align:-2px"
|
|
>≡</SPAN
|
|
></SPAN
|
|
> (identity x) <SPAN CLASS="cmsy"
|
|
><SPAN STYLE="font-size:16px;vertical-align:-2px"
|
|
>≡</SPAN
|
|
></SPAN
|
|
> x</PRE
|
|
></DD
|
|
></DL
|
|
></DIV
|
|
></DIV
|
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><DIV CLASS="footer"
|
|
><DIV CLASS="btmnav"
|
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><A HREF="t_eql.html" CLASS="prev"
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>←</A
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><A HREF="f_deftype.html" CLASS="next"
|
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>→</A
|
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><DIV CLASS="trail"
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>Conversion to HTML copyright 2023 by Gilbert Baumann</DIV
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