Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p><code>g++</code> is actually correct here; you haven't declared <code>T</code> or <code>Allocator</code> in this scope. The template declaration you have</p> <pre><code>template&lt;template &lt;class T, class Allocator&gt; class listPlaceholder&gt; void function(std::list&lt;T, Allocator&gt; param) </code></pre> <p>Says "I am parameterized over a class template that takes in two classes as arguments." However, the names of those arguments can't be accessed anywhere in the body of the template. They're mostly there as placeholders, and the above template declaration is equivalent to</p> <pre><code>template&lt;template &lt;class, class&gt; class listPlaceholder&gt; void function(std::list&lt;T, Allocator&gt; param) </code></pre> <p>This is similar to how if you were to declare a regular C++ function that took another function as an argument, you can't access the names of the parameters. For example, this is illegal:</p> <pre><code>void DoSomething(void function(int x, int y)) { x = 5; // Error! } </code></pre> <p>Since it's equivalent to</p> <pre><code>void DoSomething(void function(int, int)) { x = 5; // Error! } </code></pre> <p>I believe what you want to do is change your template function signature to look like this:</p> <pre><code>template&lt;class T, class Allocator&gt; void function(std::list&lt;T, Allocator&gt; param) </code></pre> <p>This says "This function is parameterized over two types. When provided as an argument a <code>std::list</code> parameterized over a type and an allocator, the body of this function can refer to those types as <code>T</code> and <code>Allocator</code>."</p>
    singulars
    1. This table or related slice is empty.
    1. POSpecialising a template to include template templates
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. UStemplatetypedef
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThanks, this explains the problem well. Does this mean that I will have to re-declare the original function with no specialisation but with these extra template parameters, then specialise the 2 template function into the list? How would you go about achieving the same result with a 1 template class, without it being confused with the original function?
      singulars
      1. PO
      1. USfuseinabowl
    2. COIf you wanted to have a generic "something other than list" function and a more specialized "only for lists" function, then you would write the first version as a template function that takes in some type `T` and the second function as above. C++ will always pick the more specialized function during overload resolution.
      singulars
      1. PO
      1. UStemplatetypedef
    3. COThank you for your help, it was very useful :)
      singulars
      1. PO
      1. USfuseinabowl
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload