[CF 5787] v1 - doc: Some copy-editing around prefix operators

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https://commitfest.postgresql.org/patch/5787

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Patch(es): https://www.postgresql.org/message-id/aAtpbnQphv4LWAye@msg.df7cb.de
Author(s): Christoph Berg

Author: Commitfest Bot

doc/src/sgml/ref/create_operator.sgml

@@ -23,7 +23,7 @@ PostgreSQL documentation
 <synopsis>
 CREATE OPERATOR <replaceable>name</replaceable> (
     {FUNCTION|PROCEDURE} = <replaceable class="parameter">function_name</replaceable>
-    [, LEFTARG = <replaceable class="parameter">left_type</replaceable> ] [, RIGHTARG = <replaceable class="parameter">right_type</replaceable> ]
+    [, LEFTARG = <replaceable class="parameter">left_type</replaceable> ] , RIGHTARG = <replaceable class="parameter">right_type</replaceable>
     [, COMMUTATOR = <replaceable class="parameter">com_op</replaceable> ] [, NEGATOR = <replaceable class="parameter">neg_op</replaceable> ]
     [, RESTRICT = <replaceable class="parameter">res_proc</replaceable> ] [, JOIN = <replaceable class="parameter">join_proc</replaceable> ]
     [, HASHES ] [, MERGES ]
@@ -88,8 +88,8 @@ CREATE OPERATOR <replaceable>name</replaceable> (
 
   <para>
    For binary operators, both <literal>LEFTARG</literal> and
-   <literal>RIGHTARG</literal> must be defined.  For prefix operators only
-   <literal>RIGHTARG</literal> should be defined.
+   <literal>RIGHTARG</literal> must be defined.  For prefix operators, only
+   <literal>RIGHTARG</literal> must be defined.
    The <replaceable class="parameter">function_name</replaceable>
    function must have been previously defined using <command>CREATE
    FUNCTION</command> and must be defined to accept the correct number

doc/src/sgml/xoper.sgml

@@ -21,7 +21,7 @@
 
   <para>
    <productname>PostgreSQL</productname> supports prefix
-   and infix operators.  Operators can be
+   and binary (or infix) operators.  Operators can be
    overloaded;<indexterm><primary>overloading</primary><secondary>operators</secondary></indexterm>
    that is, the same operator name can be used for different operators
    that have different numbers and types of operands.  When a query is