请教全字段模糊搜索中创建record_to_text报错

[yizenghui]

trafficstars

德哥的文章已经写得非常详细了，但我在学习过程中出现了一点小小的问题，而无法创建record_to_text函数

search_text=# create table t(phonenum text, info text, c1 int, c2 text, c3 text, c4 timestamp); 
Command OK

search_text=# insert into t values ('13888888888','i am digoal, a postgresqler',123,'china','中华人民共和国，阿里巴巴，阿',now());    
Command OK - 1 row affected

search_text=# select * from t;    
+-------------+-----------------------------+-----+-------+------------------------------+-------------------------+
| phonenum    | info                        | c1  | c2    | c3                           | c4                      |
+-------------+-----------------------------+-----+-------+------------------------------+-------------------------+
| 13888888888 | i am digoal, a postgresqler | 123 | china | 中华人民共和国，阿里巴巴，阿 | 2017-06-23 14:34:09.732 |
+-------------+-----------------------------+-----+-------+------------------------------+-------------------------+
1 row in set

search_text=# create extension pg_trgm;  
Command OK

search_text=# create or replace function record_to_text(anyelement) returns text as $$  
  select $1::text;                        
$$ language sql strict immutable;  
ERROR:  unterminated dollar-quoted string at or near "$$
  select $1::text;"
LINE 1: ...ace function record_to_text(anyelement) returns text as $$
                                                                   ^
ERROR:  unterminated dollar-quoted string at or near "$$ language sql strict immutable;"
LINE 1: $$ language sql strict immutable;
        ^
search_text=# 

我不清楚自己执行中发生了什么问题，我既希望在后续的学习中理解和处理好自己的问题，也渴望得到些许帮助。

致谢！

另： 我所参考学习的文章 https://github.com/digoal/blog/blob/master/201701/20170106_04.md

[digoal]

可能你复制的代码里有隐含字符，有问题，你自己敲一遍试试。