====== Namespace std ======

The ''std'' namespace contains a collection of standard definitions for channels, data types, and other components. This can be viewed as ACT's equivalent of the C++ standard template library.

====== Functions ======

===== Parameter-type functions =====

<code act>
export function max(pint a, b) : pint;
</code>
Returns the larger of the two ''pint''s.

<code act>
export function min(pint a, b) : pint;
</code>
Returns the smaller of the two ''pint''s.

<code act>
export function ceil_log2 (pint a) : pint;
</code>
Computes the smallest power of two that is at least as large as ''a''.

<code act>
export function pow(pint n, m) : pint;
</code>
Computes the quantity ''n'' to the power of ''m''. Note that ''pint''s use 64-bit representation. 

===== Runtime Functions =====

<code act>
export template<pint W; pint N; pint taps[N]> function fib_lfsr (int<W> state) : int<W>;
</code>
Given the current ''W''-bit state of a Fibonacci-style linear feedback shift register (LFSR), compute the next state. The LFSR has ''N'' taps, and the ith tap is at location ''taps[i]''.





====== Definitions ======

<code act>
export template<pint ID, N,W>
defproc rom (chan?(int<std::ceil_log2(N)>) addr; chan!(int<W>) dout);
</code>
(This can be used after ''actsim'' is installed.)

<code act>
export template<pint N, W>
defproc ram (chan?(int<2>) rd; chan?(int<std::ceil_log2(N)>) addr;  
             chan?(int<W>) din;  chan!(int<W>) dout);
</code>

<code act>
export defcell buf_arbiter(bool? a, b; bool! u, v) ;
</code>

<code act>
export defcell ideal_arbiter(bool? a, b; bool! u, v) ;
</code>

<code act>
export template<pint N, M>
defproc arbiter(chan?(int<N>) A; chan?(int<M>) B; chan!(int<N>) Ap; chan!(int<M>) Bp);
</code>

====== Nested namespaces ======

The ''std'' namespace contains a number of nested namespaces:

  * [[data|data]]: Standard data types
  * [[channels|channels]]: Standard channel definitions
  * [[gates|gates]]: Commonly used gates
  * [[cells|cells]]: A simple synchronous standard-cell library
  * [[io|io]]: Standard I/O primitives
  * [[bit|bit]]: Bit-manipulation functions