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[on:]

I am using the queue list library from the playground http://arduino.cc/playground/Code/QueueList i have a struct datatype and would like to insert it into it but its giving me an error.

This is what I want to do
QueueList <struct> queue;

error: template argument 1 is invalid
error: invalid type in declaration before ';' token

Is there a better way to approach to linking structs in a list.

[Reply #1 on:]

Post the rest of your code.

[Reply #2 on:]

I am using the queue list library from the playground http://arduino.cc/playground/Code/QueueList i have a struct datatype and would like to insert it into it but its giving me an error.

You have a struct with some name. The struct keyword and the struct name need to be in the <>, not just the struct keyword.

[Reply #3 on:]

Thank you, worked like a charm!  I am assuming the reason for this is because each struct is a unique object, therefore the specific struct needs to be called.

[Reply #4 on:]

Each struct is a specific type. To refer to that type you use 'struct' followed by the name of your struct.

It is common to use a typedef  so that you can refer to that struct type without having to use the struct keyword; this is only a bit of syntactic sugar but means your struct behaves syntactically just like any of the basic types.

[Reply #5 on:]

It is common to use a typedef  so that you can refer to that struct type without having to use the struct keyword; this is only a bit of syntactic sugar but means your struct behaves syntactically just like any of the basic types.

... which is not necessary in C++, which arduino uses.

[Reply #6 on:]

I know this thread is old but if anyone can share an example of using a struct with QueueList I would really appreciate it.

I'm not sure how to create the member of the struct and add it to the queue.

Thanks in advance.

JB

[Reply #7 on:]

I'm not sure how to create the member of the struct and add it to the queue.

Do you mean that you do not know how to create an instance of a struct?

What does the definition of your struct look like?

[Reply #8 on:]

Actually what I meant was how do I put my struct into the queue as a list entry or member using this library...

alternatively I decided to not go with the library and just use a standard linked list that contains my struct ... as this:

Code:

// device and linked list structure
struct linkedList {
  int id;
  char *name;
  struct dev{
    int hash;
    unsigned long ts;
  }dev;
  struct linkedList *next;
}start, *node; 

For some reason I was thinking that using this library would allow me to directly access the Nth element of the list/queue, however I think I was mistaken, hence my alternative approach since I have to traverse the list either way, less overhead not using the library.

[Reply #9 on:]

For some reason I was thinking that using this library would allow me to directly access the Nth element of the list/queue, however I think I was mistaken

You can access the nth element of a list, but not the nth element of a queue. A queue is like a line of people waiting to buy tickets to a soccer match. Which person in line should be dealt with next? The first person, obviously. Where should people get in line? At the end, of course.

I don't see the advantage of a struct in a struct.