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diff --git a/docs/tutorial/list.html b/docs/tutorial/list.html index 6b423da0..2d0e9be9 100644 --- a/docs/tutorial/list.html +++ b/docs/tutorial/list.html @@ -73,7 +73,7 @@ </tr> </table> -<p>Finally, <em>strand notation</em> is a shortcut for simple lists, like one that just lists a few numbers. It's written with the <em>ligature</em> <code><span class='Ligature'>‿</span></code>, which has a higher precedence than either functions or operators (and on the BQN keyboard, the ligature is written with a backslash, then a space). A sequence of values joined with ligatures becomes a list, so that for example the following two expressions are equivalent:</p> +<p>Finally, <em>strand notation</em> is a shortcut for simple lists, like one that just lists a few numbers. It's written with the <em>ligature</em> <code><span class='Ligature'>‿</span></code>, which has a higher precedence than either functions or operators (and is typed with backslash-space on the BQN keyboard). A sequence of values joined with ligatures becomes a list, so that for example the following two expressions are equivalent:</p> <pre><span class='Bracket'>⟨</span><span class='Number'>2</span><span class='Separator'>,</span><span class='Function'>+</span><span class='Separator'>,</span><span class='Function'>-</span><span class='Bracket'>⟩</span> <span class='Number'>2</span><span class='Ligature'>‿</span><span class='Function'>+</span><span class='Ligature'>‿</span><span class='Function'>-</span> </pre> @@ -113,7 +113,7 @@ </g> </svg> -<p>Lists are just one-dimensional arrays. Types are divided into <em>data types</em>, which tend to have a subject role, and <em>operation types</em>, which tend to have a role matching their type. Also, any value that's not an array, such as everything we used in the last tutorial, is called an <em>atom</em>.</p> +<p>Lists are just one-dimensional arrays. These types are divided into <em>data types</em>, which correspond to a subject role, and <em>operation types</em>, which each have a matching role. Also, any value that's not an array, such as everything we used in the last tutorial, is called an <em>atom</em>.</p> <h2 id="arithmetic-on-lists"><a class="header" href="#arithmetic-on-lists">Arithmetic on lists</a></h2> <p>Arithmetic functions automatically apply to each element of a list argument. If both arguments are lists, they have to have the same length, and they're matched up one element at a time.</p> <a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=w7cg4p+oMiwzLDTin6kKCiJBUEwiICsgMQoKIjMxNDE1IiAtICcwJwoKNOKAvzPigL8y4oC/MSDii4YgMeKAvzLigL8z4oC/NA==">↗️</a><pre> <span class='Function'>÷</span> <span class='Bracket'>⟨</span><span class='Number'>2</span><span class='Separator'>,</span><span class='Number'>3</span><span class='Separator'>,</span><span class='Number'>4</span><span class='Bracket'>⟩</span> @@ -181,8 +181,9 @@ "reward" </pre> <p>With a left argument <code><span class='Function'>⌽</span></code> means Rotate instead, and shifts values over by the specified amount, wrapping those that go off the end to the other side. A positive value rotates to the left, and a negative one rotates right.</p> -<a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=MiDijL0g4p+oMCwxLDIsMyw04p+pCsKvMSDijL0gImJjZGVhIg==">↗️</a><pre> <span class='Number'>2</span> <span class='Function'>⌽</span> <span class='Bracket'>⟨</span><span class='Number'>0</span><span class='Separator'>,</span><span class='Number'>1</span><span class='Separator'>,</span><span class='Number'>2</span><span class='Separator'>,</span><span class='Number'>3</span><span class='Separator'>,</span><span class='Number'>4</span><span class='Bracket'>⟩</span> +<a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=MiDijL0g4p+oMCwxLDIsMyw04p+pCgrCrzEg4oy9ICJiY2RlYSI=">↗️</a><pre> <span class='Number'>2</span> <span class='Function'>⌽</span> <span class='Bracket'>⟨</span><span class='Number'>0</span><span class='Separator'>,</span><span class='Number'>1</span><span class='Separator'>,</span><span class='Number'>2</span><span class='Separator'>,</span><span class='Number'>3</span><span class='Separator'>,</span><span class='Number'>4</span><span class='Bracket'>⟩</span> ⟨ 2 3 4 0 1 ⟩ + <span class='Number'>¯1</span> <span class='Function'>⌽</span> <span class='String'>"bcdea"</span> "abcde" </pre> @@ -206,7 +207,7 @@ </tr> </table> -<p>The 1-modifier Each (<code><span class='Modifier'>¨</span></code>) applies its operand to every element of a list argument: it's the same as <code><span class='Value'>map</span></code> in a functional programming language. With two list arguments (which have to have the same length), Each pairs the corresponding elements from each, a bit like a <code><span class='Value'>zip</span></code> function. If one argument is a list and one's an atom, the atom is reused every time instead.</p> +<p>The 1-modifier Each (<code><span class='Modifier'>¨</span></code>) applies its operand to every element of a list argument, like <code><span class='Value'>map</span></code> in a functional programming language. With two list arguments, Each pairs the corresponding elements like arithmetic does, or a bit like a <code><span class='Value'>zip</span></code> function (unlike arithmetic, it only goes one level deep). If one argument is a list and one's an atom, the atom is reused every time instead.</p> <a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=4oy9wqggImFiY2Qi4oC/IkFCQ0RFRiLigL8iMDEiCgoic3RyaW5nIuKAvyJsaXN0IuKAvyJhcnJheSIg4oi+wqggJ3MnCgoiYWJjIiDii4jCqCDijL0gImFiYyI=">↗️</a><pre> <span class='Function'>⌽</span><span class='Modifier'>¨</span> <span class='String'>"abcd"</span><span class='Ligature'>‿</span><span class='String'>"ABCDEF"</span><span class='Ligature'>‿</span><span class='String'>"01"</span> ⟨ "dcba" "FEDCBA" "10" ⟩ @@ -229,7 +230,7 @@ 3 </pre> <p>With this evaluation order, <code><span class='Function'>-</span><span class='Modifier'>´</span></code> gives the <em>alternating sum</em> of its argument. Think of it this way: the left argument of each <code><span class='Function'>-</span></code> is a single number, while the right argument is made up of all the numbers to the right subtracted together. So each <code><span class='Function'>-</span></code> flips the sign of every number to its right, and every number is negated by all the <code><span class='Function'>-</span></code>s to its left. The first number (<code><span class='Number'>1</span></code> above) never gets negated, the second is negated once, the third is negated twice, returning it to its original value… the signs alternate.</p> -<p><em>Hey, isn't it dissonant that the first, second, and third numbers are negated zero, one, and two times? If they were the zeroth, first, and second it wouldn't be…</em></p> +<p><em>Hey, isn't it dissonant that the first, second, and third numbers are negated zero, one, and two times? Not if you call them the zeroth, first, and second…</em></p> <p>You can fold with the Join To function to join several lists together:</p> <a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=4oi+wrQg4p+oICJjb24iLCAiY2F0IiwgImVuYXQiLCAiZSIg4p+p">↗️</a><pre> <span class='Function'>∾</span><span class='Modifier'>´</span> <span class='Bracket'>⟨</span> <span class='String'>"con"</span><span class='Separator'>,</span> <span class='String'>"cat"</span><span class='Separator'>,</span> <span class='String'>"enat"</span><span class='Separator'>,</span> <span class='String'>"e"</span> <span class='Bracket'>⟩</span> "concatenate" @@ -239,7 +240,7 @@ "concatenate" </pre> <h2 id="example-base-decoding"><a class="header" href="#example-base-decoding">Example: base decoding</a></h2> -<p>Some people like to imagine that robots or other techno-beings speak entirely in binary-encoded ASCII, like for instance "01001110 01100101 01110010 01100100 00100001". This is dumb for a lot of reasons, and the encoded text probably just says something inane, but you're a slave to curiosity and can't ignore it. Are one and a half tutorials of BQN enough to clear your conscience?</p> +<p>Some people like to imagine that robots or other techno-beings speak entirely in binary-encoded ASCII, like for instance "01001110 01100101 01110010 01100100 00100001". This is dumb for a lot of reasons, and the encoded text probably just says something inane, but you're a slave to curiosity and can't ignore it. Are one and two-thirds tutorials of BQN enough to clear your conscience?</p> <table class='primitives'> <tr> <td><span class='Function'>↕</span></td> @@ -259,7 +260,7 @@ <a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=4oaVIDg=">↗️</a><pre> <span class='Function'>↕</span> <span class='Number'>8</span> ⟨ 0 1 2 3 4 5 6 7 ⟩ </pre> -<p>Natural numbers in BQN start at 0. I'll get to the second function in a moment, but first let's consider how we'd decode just one number in binary. I'll pick a smaller one: 9 is 1001 in binary. Like the first 1 in decimal 1001 counts for one thousand or <code><span class='Number'>10</span><span class='Function'>⋆</span><span class='Number'>3</span></code>, the first one in binary 1001 counts for 8, which is <code><span class='Number'>2</span><span class='Function'>⋆</span><span class='Number'>3</span></code>. We can put each number next to its place value like this:</p> +<p>Natural numbers in BQN start at 0. I'll get to the second primitive in a moment, but first let's consider how we'd decode just one number in binary. I'll pick a smaller one: 9 is 1001 in binary. Like the first 1 in decimal 1001 counts for one thousand or <code><span class='Number'>10</span><span class='Function'>⋆</span><span class='Number'>3</span></code>, the first one in binary 1001 counts for 8, which is <code><span class='Number'>2</span><span class='Function'>⋆</span><span class='Number'>3</span></code>. We can put each number next to its place value like this:</p> <a class="replLink" title="Open in the REPL" target="_blank" href="https://mlochbaum.github.io/BQN/try.html#code=OOKAvzTigL8y4oC/MSDii4jCqCAx4oC/MOKAvzDigL8x">↗️</a><pre> <span class='Number'>8</span><span class='Ligature'>‿</span><span class='Number'>4</span><span class='Ligature'>‿</span><span class='Number'>2</span><span class='Ligature'>‿</span><span class='Number'>1</span> <span class='Function'>⋈</span><span class='Modifier'>¨</span> <span class='Number'>1</span><span class='Ligature'>‿</span><span class='Number'>0</span><span class='Ligature'>‿</span><span class='Number'>0</span><span class='Ligature'>‿</span><span class='Number'>1</span> ⟨ ⟨ 8 1 ⟩ ⟨ 4 0 ⟩ ⟨ 2 0 ⟩ ⟨ 1 1 ⟩ ⟩ </pre> @@ -363,7 +364,7 @@ 9 </pre> <h2 id="summary"><a class="header" href="#summary">Summary</a></h2> -<p>There are three types of syntax that create lists: the <code><span class='String'>"string literal"</span></code> for lists of characters and either enclosing angle brackets <code><span class='Bracket'>⟨⟩</span></code> with <code><span class='Separator'>,</span></code> or <code><span class='Separator'>⋄</span></code> or newline characters or connecting ligatures <code><span class='Ligature'>‿</span></code> for lists with arbitrary elements. The ligature has a higher precedence than functions or modifiers, so we should add it to our precedence table:</p> +<p>There are three types of syntax that create lists. <code><span class='String'>"string literal"</span></code> gives a list of characters. For arbitrary lists, use enclosing angle brackets <code><span class='Bracket'>⟨⟩</span></code> with <code><span class='Separator'>,</span></code> or <code><span class='Separator'>⋄</span></code> or newline between elements, or just connect elements with ligatures <code><span class='Ligature'>‿</span></code>. The ligature has a higher precedence than functions or modifiers and might require parentheses, so we should add it to our precedence table:</p> <table> <thead> <tr> @@ -395,8 +396,8 @@ </tr> </tbody> </table> -<p>The elements of a list can have any syntactic role; it's ignored and the list as a whole is a subject.</p> -<p>We introduced a few new primitives. The links below go to the full documentation pages for them.</p> +<p>The elements of a list can have any syntactic role. It's ignored and the list as a whole is a subject.</p> +<p>We introduced a few new primitives. The links in the table go to their full documentation pages.</p> <table> <thead> <tr> @@ -438,5 +439,5 @@ </tr> </tbody> </table> -<p>Additionally, we saw that the arithmetic functions work naturally on lists, automatically applying to every element of a single list argument or pairing up the elements of two list arguments.</p> +<p>And we saw that the arithmetic functions work naturally on lists, automatically applying to every element of a single list argument or pairing up the elements of two list arguments.</p> <p>Even this small amount of list functionality is enough to tackle some little problems. We haven't even introduced a function notation yet!</p> |