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diff --git a/docs/00.html b/docs/00.html new file mode 100644 index 0000000..b32be13 --- /dev/null +++ b/docs/00.html @@ -0,0 +1,71 @@ +<!DOCTYPE html> +<html> +<head> +<link rel="stylesheet" href="docs.css"> +<title>Declarations</title> +</head> +<body> +<h2>Declarations</h2> + +<p><a href="contents.html">Table of contents</a> · <a href="01.html">Next</a></p> + +Variable declarations have the following syntax: +<pre> +<name> :[:] [type] [= expression]; +</pre> + +<p>The square brackets (<c>[]</c>) indicate something optional.</p> + +<p> +All of the following statements +declare an new variable <c>x</c> which is an integer, and has a value of 0: +<pre> +x : int; +x : int = 0; +x := 0; +</pre> +Note that in the first of those statements, although no expression +is specified, it defaults to 0. +</p> + +<p>If you wanted <c>x</c> to be a floating-point number, you could use:</p> + +<pre> +x : float; +x : float = 0; +x := 0.0; +</pre> + +<p>Note that <c>0</c> can be used as both a <c>float</c> and an <c>int</c>eger, but +when no type is specified, it defaults to an <c>int</c>, whereas <c>0.0</c> +defaults to a <c>float</c>.</p> + +<p>Here are all of toc's basic builtin types and their ranges of values:</p> + +<ul> +<li><c>int</c> - A 64-bit signed integer (always), -9223372036854775808 to 9223372036854775807</li> +<li><c>i8</c> - An 8-bit signed integer, -128 to 128</li> +<li><c>i16</c> - 16-bit signed integer, -32768 to 32767</li> +<li><c>i32</c> - 32-bit signed integer, -2147483648 to 2147483647</li> +<li><c>i64</c> - 64-bit signed integer (same as <c>int</c>, but more explicit about the size), -9223372036854775808 to 9223372036854775807</li> +<li><c>u8</c> - An 8-bit unsigned integer, 0 to 255</li> +<li><c>u16</c> - 16-bit unsigned integer, 0 to 65535</li> +<li><c>u32</c> - 32-bit unsigned integer, 0 to 4294967295</li> +<li><c>u64</c> - 64-bit unsigned integer, 0 to 18446744073709551615</li> +<li><c>float</c> - A 32-bit floating-point number, -3.40282347e+38 to 3.40282347e+38</li> +<li><c>f32</c> - A 32-bit floating-point number (same as <c>float</c>, but more explicit about the size)</li> +<li><c>f64</c> - A 64-bit floating-point number, -1.7976931348623157e+308 to 1.7976931348623157e+308</li> +<li><c>bool</c> - A boolean value, either <c>false</c> or <c>true</c>.</li> +<li><c>char</c> - A character (usually either -128 to 127 or 0 to 255).</li> +</ul> + +<p>To make declarations constant, use <c>::</c> instead of <c>:</c>. e.g.</p> + +<p><c> +x ::= 5+3; +y :: float = 5.123; +</c></p> + +<p>Here, "constant" means constant at compile time, not read-only as it does in C. One interesting thing about toc is that normal functions can run at compile time, so pretty much any expression is a valid initializer for a constant, e.g. doing <c>x ::= some_function();</c> runs <c>some_function</c> at compile time, not at run time.</p> +</body> +</html> |