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-rw-r--r--railties/doc/guides/html/activerecord_validations_callbacks.html81
1 files changed, 52 insertions, 29 deletions
diff --git a/railties/doc/guides/html/activerecord_validations_callbacks.html b/railties/doc/guides/html/activerecord_validations_callbacks.html
index cb381e7191..039e3d1891 100644
--- a/railties/doc/guides/html/activerecord_validations_callbacks.html
+++ b/railties/doc/guides/html/activerecord_validations_callbacks.html
@@ -231,7 +231,7 @@ ul#navMain {
<li><a href="#_the_tt_validates_length_of_tt_helper">The <tt>validates_length_of</tt> helper</a></li>
- <li><a href="#_the_tt_validates_numericallity_of_tt_helper">The <tt>validates_numericallity_of</tt> helper</a></li>
+ <li><a href="#_the_tt_validates_numericality_of_tt_helper">The <tt>validates_numericality_of</tt> helper</a></li>
<li><a href="#_the_tt_validates_presence_of_tt_helper">The <tt>validates_presence_of</tt> helper</a></li>
@@ -338,7 +338,7 @@ Create your own custom validation methods
</li>
<li>
<p>
-Work with the error messages generated by the validation proccess
+Work with the error messages generated by the validation process
</p>
</li>
<li>
@@ -405,7 +405,7 @@ http://www.gnu.org/software/src-highlite -->
&gt;&gt; p.new_record?
=&gt; false</tt></pre>
</div></div>
-<div class="para"><p>Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either <tt>save</tt> or <tt>update_attributes</tt>) will result in a SQL update operation. Active Record will use this facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.</p></div>
+<div class="para"><p>Saving new records means sending an SQL insert operation to the database, while saving existing records (by calling either <tt>save</tt> or <tt>update_attributes</tt>) will result in a SQL update operation. Active Record will use these facts to perform validations upon your objects, avoiding then to be recorded to the database if their inner state is invalid in some way. You can specify validations that will be beformed every time a object is saved, just when you're creating a new record or when you're updating an existing one.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
@@ -524,7 +524,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> MovieFile <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_exclusion_of <span style="color: #990000">:</span>format<span style="color: #990000">,</span> <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">in</span></span> <span style="color: #990000">=&gt;</span> <span style="color: #990000">%</span>w<span style="color: #990000">(</span>mov avi<span style="color: #990000">),</span> <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Extension %s is not allowed"</span>
+ validates_exclusion_of <span style="color: #990000">:</span>format<span style="color: #990000">,</span> <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">in</span></span> <span style="color: #990000">=&gt;</span> <span style="color: #990000">%</span>w<span style="color: #990000">(</span>mov avi<span style="color: #990000">),</span>
+ <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Extension %s is not allowed"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The <tt>validates_exclusion_of</tt> helper has an option <tt>:in</tt> that receives the set of values that will not be accepted for the validated attributes. The <tt>:in</tt> option has an alias called <tt>:within</tt> that you can use for the same purpose, if you'd like to. In the previous example we used the <tt>:message</tt> option to show how we can personalize it with the current attribute's value, through the <tt>%s</tt> format mask.</p></div>
@@ -537,7 +538,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Product <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_format_of <span style="color: #990000">:</span>description<span style="color: #990000">,</span> <span style="color: #990000">:</span>with <span style="color: #990000">=&gt;</span> <span style="color: #FF6600">/^[a-zA-Z]+$/</span><span style="color: #990000">,</span> <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Only letters allowed"</span>
+ validates_format_of <span style="color: #990000">:</span>description<span style="color: #990000">,</span> <span style="color: #990000">:</span>with <span style="color: #990000">=&gt;</span> <span style="color: #FF6600">/^[a-zA-Z]+$/</span><span style="color: #990000">,</span>
+ <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Only letters allowed"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The default error message for <tt>validates_format_of</tt> is "<em>is invalid</em>".</p></div>
@@ -549,7 +551,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Coffee <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_inclusion_of <span style="color: #990000">:</span>size<span style="color: #990000">,</span> <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">in</span></span> <span style="color: #990000">=&gt;</span> <span style="color: #990000">%</span>w<span style="color: #990000">(</span>small medium large<span style="color: #990000">),</span> <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"%s is not a valid size"</span>
+ validates_inclusion_of <span style="color: #990000">:</span>size<span style="color: #990000">,</span> <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">in</span></span> <span style="color: #990000">=&gt;</span> <span style="color: #990000">%</span>w<span style="color: #990000">(</span>small medium large<span style="color: #990000">),</span>
+ <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"%s is not a valid size"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>The <tt>validates_inclusion_of</tt> helper has an option <tt>:in</tt> that receives the set of values that will be accepted. The <tt>:in</tt> option has an alias called <tt>:within</tt> that you can use for the same purpose, if you'd like to. In the previous example we used the <tt>:message</tt> option to show how we can personalize it with the current attribute's value, through the <tt>%s</tt> format mask.</p></div>
@@ -602,7 +605,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>This helper has an alias called <tt>validates_size_of</tt>, it's the same helper with a different name. You can use it if you'd like to.</p></div>
-<h3 id="_the_tt_validates_numericallity_of_tt_helper">3.9. The <tt>validates_numericallity_of</tt> helper</h3>
+<h3 id="_the_tt_validates_numericality_of_tt_helper">3.9. The <tt>validates_numericality_of</tt> helper</h3>
<div class="para"><p>This helper validates that your attributes have only numeric values. By default, it will match an optional sign followed by a integral or floating point number. Using the <tt>:integer_only</tt> option set to true, you can specify that only integral numbers are allowed.</p></div>
<div class="para"><p>If you use <tt>:integer_only</tt> set to <tt>true</tt>, then it will use the <tt><span>/\A[+\-]?\d+\Z/</span></tt> regular expression to validate the attribute's value. Otherwise, it will try to convert the value using <tt>Kernel.Float</tt>.</p></div>
<div class="listingblock">
@@ -611,11 +614,11 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Player <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_numericallity_of <span style="color: #990000">:</span>points
- validates_numericallity_of <span style="color: #990000">:</span>games_played<span style="color: #990000">,</span> <span style="color: #990000">:</span>integer_only <span style="color: #990000">=&gt;</span> <span style="font-weight: bold"><span style="color: #0000FF">true</span></span>
+ validates_numericality_of <span style="color: #990000">:</span>points
+ validates_numericality_of <span style="color: #990000">:</span>games_played<span style="color: #990000">,</span> <span style="color: #990000">:</span>integer_only <span style="color: #990000">=&gt;</span> <span style="font-weight: bold"><span style="color: #0000FF">true</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
-<div class="para"><p>The default error message for <tt>validates_numericallity_of</tt> is "<em>is not a number</em>".</p></div>
+<div class="para"><p>The default error message for <tt>validates_numericality_of</tt> is "<em>is not a number</em>".</p></div>
<h3 id="_the_tt_validates_presence_of_tt_helper">3.10. The <tt>validates_presence_of</tt> helper</h3>
<div class="para"><p>This helper validates that the attributes are not empty. It uses the <tt>blank?</tt> method to check if the value is either <tt>nil</tt> or an empty string (if the string has only spaces, it will still be considered empty).</p></div>
<div class="listingblock">
@@ -673,7 +676,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Holiday <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_uniqueness_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>scope <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>year<span style="color: #990000">,</span> <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Should happen once per year"</span>
+ validates_uniqueness_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>scope <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>year<span style="color: #990000">,</span>
+ <span style="color: #990000">:</span>message <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"Should happen once per year"</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<div class="para"><p>There is also a <tt>:case_sensitive</tt> option that you can use to define if the uniqueness contraint will be case sensitive or not. This option defaults to true.</p></div>
@@ -692,7 +696,7 @@ http://www.gnu.org/software/src-highlite -->
<div class="sectionbody">
<div class="para"><p>There are some common options that all the validation helpers can use. Here they are, except for the <tt>:if</tt> and <tt>:unless</tt> options, which we'll cover right at the next topic.</p></div>
<h3 id="_the_tt_allow_nil_tt_option">4.1. The <tt>:allow_nil</tt> option</h3>
-<div class="para"><p>You may use the <tt>:allow_nil</tt> option everytime you just want to trigger a validation if the value being validated is not <tt>nil</tt>. You may be asking yourself if it makes any sense to use <tt>:allow_nil</tt> and <tt>validates_presence_of</tt> together. Well, it does. Remember, validation will be skipped only for <tt>nil</tt> attributes, but empty strings are not considered <tt>nil</tt>.</p></div>
+<div class="para"><p>You may use the <tt>:allow_nil</tt> option everytime you want to trigger a validation only if the value being validated is not <tt>nil</tt>. You may be asking yourself if it makes any sense to use <tt>:allow_nil</tt> and <tt>validates_presence_of</tt> together. Well, it does. Remember, validation will be skipped only for <tt>nil</tt> attributes, but empty strings are not considered <tt>nil</tt>.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@@ -713,9 +717,14 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Person <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_uniqueness_of <span style="color: #990000">:</span>email<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>create <span style="font-style: italic"><span style="color: #9A1900"># =&gt; it will be possible to update email with a duplicated value</span></span>
- validates_numericallity_of <span style="color: #990000">:</span>age<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>update <span style="font-style: italic"><span style="color: #9A1900"># =&gt; it will be possible to create the record with a 'non-numerical age'</span></span>
- validates_presence_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>save <span style="font-style: italic"><span style="color: #9A1900"># =&gt; that's the default</span></span>
+ <span style="font-style: italic"><span style="color: #9A1900"># =&gt; it will be possible to update email with a duplicated value</span></span>
+ validates_uniqueness_of <span style="color: #990000">:</span>email<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>create
+
+ <span style="font-style: italic"><span style="color: #9A1900"># =&gt; it will be possible to create the record with a 'non-numerical age'</span></span>
+ validates_numericality_of <span style="color: #990000">:</span>age<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>update
+
+ <span style="font-style: italic"><span style="color: #9A1900"># =&gt; the default</span></span>
+ validates_presence_of <span style="color: #990000">:</span>name<span style="color: #990000">,</span> <span style="color: #990000">:</span>on <span style="color: #990000">=&gt;</span> <span style="color: #990000">:</span>save
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
</div>
@@ -756,7 +765,8 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Account <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validates_confirmation_of <span style="color: #990000">:</span>password<span style="color: #990000">,</span> <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">unless</span></span> <span style="color: #990000">=&gt;</span> Proc<span style="color: #990000">.</span>new <span style="color: #FF0000">{</span> <span style="color: #990000">|</span>a<span style="color: #990000">|</span> a<span style="color: #990000">.</span>password<span style="color: #990000">.</span>blank? <span style="color: #FF0000">}</span>
+ validates_confirmation_of <span style="color: #990000">:</span>password<span style="color: #990000">,</span>
+ <span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #0000FF">unless</span></span> <span style="color: #990000">=&gt;</span> Proc<span style="color: #990000">.</span>new <span style="color: #FF0000">{</span> <span style="color: #990000">|</span>a<span style="color: #990000">|</span> a<span style="color: #990000">.</span>password<span style="color: #990000">.</span>blank? <span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
</div>
@@ -770,7 +780,8 @@ http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Invoice <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> validate_on_create
- errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>expiration_date<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be in the past"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">!</span>expiration_date<span style="color: #990000">.</span>blank? <span style="font-weight: bold"><span style="color: #0000FF">and</span></span> expiration_date <span style="color: #990000">&lt;</span> Date<span style="color: #990000">.</span>today
+ errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>expiration_date<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be in the past"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span>
+ <span style="color: #990000">!</span>expiration_date<span style="color: #990000">.</span>blank? <span style="font-weight: bold"><span style="color: #0000FF">and</span></span> expiration_date <span style="color: #990000">&lt;</span> Date<span style="color: #990000">.</span>today
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
@@ -781,14 +792,17 @@ by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #0000FF">class</span></span> Invoice <span style="color: #990000">&lt;</span> ActiveRecord<span style="color: #990000">::</span>Base
- validate <span style="color: #990000">:</span>expiration_date_cannot_be_in_the_past<span style="color: #990000">,</span> <span style="color: #990000">:</span>discount_cannot_be_more_than_total_value
+ validate <span style="color: #990000">:</span>expiration_date_cannot_be_in_the_past<span style="color: #990000">,</span>
+ <span style="color: #990000">:</span>discount_cannot_be_more_than_total_value
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> expiration_date_cannot_be_in_the_past
- errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>expiration_date<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be in the past"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">!</span>expiration_date<span style="color: #990000">.</span>blank? <span style="font-weight: bold"><span style="color: #0000FF">and</span></span> expiration_date <span style="color: #990000">&lt;</span> Date<span style="color: #990000">.</span>today
+ errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>expiration_date<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be in the past"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">if</span></span>
+ <span style="color: #990000">!</span>expiration_date<span style="color: #990000">.</span>blank? <span style="font-weight: bold"><span style="color: #0000FF">and</span></span> expiration_date <span style="color: #990000">&lt;</span> Date<span style="color: #990000">.</span>today
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">def</span></span> discount_cannot_be_greater_than_total_value
- errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>discount<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be greater than total value"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">unless</span></span> discount <span style="color: #990000">&lt;=</span> total_value
+ errors<span style="color: #990000">.</span>add<span style="color: #990000">(:</span>discount<span style="color: #990000">,</span> <span style="color: #FF0000">"can't be greater than total value"</span><span style="color: #990000">)</span> <span style="font-weight: bold"><span style="color: #0000FF">unless</span></span>
+ discount <span style="color: #990000">&lt;=</span> total_value
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
@@ -874,16 +888,18 @@ person<span style="color: #990000">.</span>errors<span style="color: #990000">.<
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new<span style="color: #990000">(:</span>name <span style="color: #990000">=&gt;</span> <span style="color: #FF0000">"JD"</span><span style="color: #990000">)</span>
person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
-person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; "is too short (minimum is 3 characters)"</span></span>
+person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span>
+<span style="font-style: italic"><span style="color: #9A1900"># =&gt; "is too short (minimum is 3 characters)"</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new
person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
-person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
+person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span>
+<span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
</tt></pre></div></div>
<div class="ilist"><ul>
<li>
<p>
-<tt>clear</tt> is used when you intentionally wants to clear all the messages in the <tt>errors</tt> collection.
+<tt>clear</tt> is used when you intentionally want to clear all the messages in the <tt>errors</tt> collection. However, calling <tt>errors.clear</tt> upon an invalid object won't make it valid: the <tt>errors</tt> collection will now be empty, but the next time you call <tt>valid?</tt> or any method that tries to save this object to the database, the validations will run. If any of them fails, the <tt>errors</tt> collection will get filled again.
</p>
</li>
</ul></div>
@@ -898,10 +914,15 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
person <span style="color: #990000">=</span> Person<span style="color: #990000">.</span>new
-puts person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
-person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span> <span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
+person<span style="color: #990000">.</span>valid? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
+person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span>
+<span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
+
person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>clear
-person<span style="color: #990000">.</span>errors <span style="font-style: italic"><span style="color: #9A1900"># =&gt; nil</span></span>
+person<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>empty? <span style="font-style: italic"><span style="color: #9A1900"># =&gt; true</span></span>
+p<span style="color: #990000">.</span>save <span style="font-style: italic"><span style="color: #9A1900"># =&gt; false</span></span>
+p<span style="color: #990000">.</span>errors<span style="color: #990000">.</span>on<span style="color: #990000">(:</span>name<span style="color: #990000">)</span>
+<span style="font-style: italic"><span style="color: #9A1900"># =&gt; ["can't be blank", "is too short (minimum is 3 characters)"]</span></span>
</tt></pre></div></div>
</div>
<h2 id="_callbacks">8. Callbacks</h2>
@@ -910,7 +931,7 @@ person<span style="color: #990000">.</span>errors <span style="font-style: itali
<h3 id="_callbacks_registration">8.1. Callbacks registration</h3>
<div class="para"><p>In order to use the available callbacks, you need to registrate them. There are two ways of doing that.</p></div>
<h3 id="_registering_callbacks_by_overriding_the_callback_methods">8.2. Registering callbacks by overriding the callback methods</h3>
-<div class="para"><p>You can specify the callback method direcly, by overriding it. Let's see how it works using the <tt>before_validation</tt> callback, which will surprisingly run right before any validation is done.</p></div>
+<div class="para"><p>You can specify the callback method directly, by overriding it. Let's see how it works using the <tt>before_validation</tt> callback, which will surprisingly run right before any validation is done.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@@ -1094,7 +1115,7 @@ Readability, since your callback declarations will live at the beggining of your
</div>
<h2 id="_halting_execution">10. Halting Execution</h2>
<div class="sectionbody">
-<div class="para"><p>As you start registering new callbacks for your models, they will be queued for execution. This queue will include all your model's validations, the registered callbacks and the database operation to be executed. However, if at any moment one of the callback methods returns a boolean <tt>false</tt> (not <tt>nil</tt>) value, this execution chain will be halted and the desired operation will not complete: your model will not get persisted in the database, or your records will not get deleted and so on.</p></div>
+<div class="para"><p>As you start registering new callbacks for your models, they will be queued for execution. This queue will include all your model's validations, the registered callbacks and the database operation to be executed. However, if at any moment one of the <tt>before_create</tt>, <tt>before_save</tt>, <tt>before_update</tt> or <tt>before_destroy</tt> callback methods returns a boolean <tt>false</tt> (not <tt>nil</tt>) value, this execution chain will be halted and the desired operation will not complete: your model will not get persisted in the database, or your records will not get deleted and so on.</p></div>
</div>
<h2 id="_callback_classes">11. Callback classes</h2>
<div class="sectionbody">
@@ -1174,7 +1195,7 @@ http://www.gnu.org/software/src-highlite -->
<span style="font-weight: bold"><span style="color: #0000FF">end</span></span>
</tt></pre></div></div>
<h3 id="_registering_observers">12.1. Registering observers</h3>
-<div class="para"><p>If you payed attention, you may be wondering where Active Record Observers are referenced in our applications, so they get instantiate and begin to interact with our models. For observers to work we need to register then in our application's <strong>config/environment.rb</strong> file. In this file there is a commented out line where we can define the observers that our application should load at start-up.</p></div>
+<div class="para"><p>If you payed attention, you may be wondering where Active Record Observers are referenced in our applications, so they get instantiate and begin to interact with our models. For observers to work we need to register them somewhere. The usual place to do that is in our application's <strong>config/environment.rb</strong> file. In this file there is a commented out line where we can define the observers that our application should load at start-up.</p></div>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 2.9
by Lorenzo Bettini
@@ -1183,6 +1204,8 @@ http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-style: italic"><span style="color: #9A1900"># Activate observers that should always be running</span></span>
config<span style="color: #990000">.</span>active_record<span style="color: #990000">.</span>observers <span style="color: #990000">=</span> <span style="color: #990000">:</span>registration_observer<span style="color: #990000">,</span> <span style="color: #990000">:</span>auditor
</tt></pre></div></div>
+<div class="para"><p>You can uncomment the line with <tt>config.active_record.observers</tt> and change the symbols for the name of the observers that should be registered.</p></div>
+<div class="para"><p>It's also possible to register callbacks in any of the files living at <strong>config/environments/</strong>, if you want an observer to work only in a specific environment. There is not a <tt>config.active_record.observers</tt> line at any of those files, but you can simply add it.</p></div>
<h3 id="_where_to_put_the_observers_source_files">12.2. Where to put the observers' source files</h3>
<div class="para"><p>By convention, you should always save your observers' source files inside <strong>app/models</strong>.</p></div>
</div>