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<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../inform7n.html">Inform7</a></li><li><a href="index.html">runtime</a></li><li><a href="index.html#4">Chapter 4: Enclosed Resources</a></li><li><b>Text Literals</b></li></ul></div>
<p class="purpose">In this section we compile text constants.</p>
<ul class="toc"><li><a href="4-tl.html#SP1">&#167;1. Runtime representation</a></li><li><a href="4-tl.html#SP2">&#167;2. Default value</a></li><li><a href="4-tl.html#SP3">&#167;3. Suppressing apostrophe substitution</a></li><li><a href="4-tl.html#SP4">&#167;4. Making literals</a></li></ul><hr class="tocbar">
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>&#167;1. Runtime representation. </b>Literal texts arise from source text such as:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">let</span><span class="plain-syntax"> </span><span class="identifier-syntax">Q</span><span class="plain-syntax"> </span><span class="identifier-syntax">be</span><span class="plain-syntax"> </span><span class="string-syntax">"the quick brown fox"</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">say</span><span class="plain-syntax"> </span><span class="string-syntax">"Where has that indolent hound got to?"</span><span class="plain-syntax">;</span>
</pre>
<p class="commentary">Note that only <span class="extract"><span class="extract-syntax">"the quick brown fox"</span></span> is actually a constant value here; the
text concerning the hound is turned directly into operands for Inter instructions
for printing text, and never needs to be a value. The fox text, on the other hand,
is being stored in <span class="extract"><span class="extract-syntax">Q</span></span>, and you can only store values.
</p>
<p class="commentary">Text at runtime is stored in small blocks, always of size 2:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> small block:</span>
<span class="plain-syntax"> Q ----------------&gt; format</span>
<span class="plain-syntax"> content</span>
</pre>
<p class="commentary">The format can be one of four possible alternatives at runtime, and the runtime
system may dynamically switch between them; essentially it uses this to
decompress text from its "packed" form to a character-accessible form only
on demand.
</p>
<p class="commentary">The compiler generates only one of these formats: <span class="extract"><span class="extract-syntax">CONSTANT_PACKED_TEXT_STORAGE</span></span>.
In this format, the <span class="extract"><span class="extract-syntax">content</span></span> can be either a packed string, or a function,
so although there is no long block to make, we do always have something else
to make besides the small block.
</p>
<p class="commentary">In this section, <span class="extract"><span class="extract-syntax">content</span></span> will always be a packed string; in <a href="4-ts.html" class="internal">Text Substitutions</a>
it will always be a function.
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="function-syntax">TextLiterals::small_block</span><button class="popup" onclick="togglePopup('usagePopup1')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup1">Usage of <span class="code-font"><span class="function-syntax">TextLiterals::small_block</span></span>:<br/><a href="4-tl.html#SP2">&#167;2</a>, <a href="4-tl.html#SP4">&#167;4</a><br/>Group Together - <a href="4-gt.html#SP2">&#167;2</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">content</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">small_block</span><span class="plain-syntax"> = </span><a href="4-enc.html#SP2" class="function-link"><span class="function-syntax">Enclosures::new_small_block_for_constant</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="4-tl.html#SP1" class="function-link"><span class="function-syntax">TextLiterals::compile_value_to</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">small_block</span><span class="plain-syntax">, </span><span class="identifier-syntax">content</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">small_block</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">TextLiterals::compile_value_to</span><button class="popup" onclick="togglePopup('usagePopup2')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup2">Usage of <span class="code-font"><span class="function-syntax">TextLiterals::compile_value_to</span></span>:<br/>Responses - <a href="4-rsp.html#SP6">&#167;6</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">at</span><span class="plain-syntax">, </span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">content</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">packaging_state</span><span class="plain-syntax"> </span><span class="identifier-syntax">save</span><span class="plain-syntax"> = </span><a href="2-ea.html#SP2" class="function-link"><span class="function-syntax">EmitArrays::begin_unchecked</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">at</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP4" class="function-link"><span class="function-syntax">EmitArrays::iname_entry</span></a><span class="plain-syntax">(</span><a href="2-hrr.html#SP11" class="function-link"><span class="function-syntax">Hierarchy::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">CONSTANT_PACKED_TEXT_STORAGE_HL</span><span class="plain-syntax">));</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP4" class="function-link"><span class="function-syntax">EmitArrays::iname_entry</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">content</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP5" class="function-link"><span class="function-syntax">EmitArrays::end</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">save</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>&#167;2. Default value. </b>The default text is empty:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="function-syntax">TextLiterals::default_text</span><button class="popup" onclick="togglePopup('usagePopup3')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup3">Usage of <span class="code-font"><span class="function-syntax">TextLiterals::default_text</span></span>:<br/><a href="4-tl.html#SP4">&#167;4</a><br/>Default Values - <a href="2-dv.html#SP2_2">&#167;2.2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="4-tl.html#SP1" class="function-link"><span class="function-syntax">TextLiterals::small_block</span></a><span class="plain-syntax">(</span><a href="2-hrr.html#SP11" class="function-link"><span class="function-syntax">Hierarchy::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">EMPTY_TEXT_PACKED_HL</span><span class="plain-syntax">));</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP3" class="paragraph-anchor"></a><b>&#167;3. Suppressing apostrophe substitution. </b>We are allowed to flag one text where ordinary apostrophe-to-double-quote
substitution doesn't occur: this is used for the title at the top of the
source text, and nothing else.
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">wn_quote_suppressed</span><span class="plain-syntax"> = -1;</span>
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">TextLiterals::suppress_quote_expansion</span><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">wn_quote_suppressed</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Wordings::first_wn</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">TextLiterals::suppressing_on</span><button class="popup" onclick="togglePopup('usagePopup4')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup4">Usage of <span class="code-font"><span class="function-syntax">TextLiterals::suppressing_on</span></span>:<br/><a href="4-tl.html#SP4">&#167;4</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">wn_quote_suppressed</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0</span><span class="plain-syntax">) &amp;&amp;</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Wordings::first_wn</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">) == </span><span class="identifier-syntax">wn_quote_suppressed</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP4" class="paragraph-anchor"></a><b>&#167;4. Making literals. </b>This was once a rather elegantly complicated algorithm involving searches on
a red-black tree in order to compile the texts in alphabetical order, but in
April 2021 that was replaced by an Inter pipeline stage which collates the text
much later in the process. See <a href="../pipeline-module/5-lt.html" class="internal">Literal Text (in pipeline)</a>.
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="function-syntax">TextLiterals::to_value</span><button class="popup" onclick="togglePopup('usagePopup5')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup5">Usage of <span class="code-font"><span class="function-syntax">TextLiterals::to_value</span></span>:<br/>Emit - <a href="2-emt.html#SP9">&#167;9</a><br/>Stored Action Literals - <a href="4-sal.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="4-tl.html#SP4" class="function-link"><span class="function-syntax">TextLiterals::to_value_inner</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">, </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
<span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="function-syntax">TextLiterals::to_value_unescaped</span><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="4-tl.html#SP4" class="function-link"><span class="function-syntax">TextLiterals::to_value_inner</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">, </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
<span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="function-syntax">TextLiterals::to_value_inner</span><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">unesc</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">w1</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Wordings::first_wn</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Wide::cmp</span><span class="plain-syntax">(</span><span class="identifier-syntax">Lexer::word_text</span><span class="plain-syntax">(</span><span class="identifier-syntax">w1</span><span class="plain-syntax">), </span><span class="identifier-syntax">U</span><span class="string-syntax">"\"\""</span><span class="plain-syntax">) == </span><span class="constant-syntax">0</span><span class="plain-syntax">)</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="4-tl.html#SP2" class="function-link"><span class="function-syntax">TextLiterals::default_text</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">content_iname</span><span class="plain-syntax"> = </span><a href="4-enc.html#SP1" class="function-link"><span class="function-syntax">Enclosures::new_iname</span></a><span class="plain-syntax">(</span><span class="constant-syntax">LITERALS_HAP</span><span class="plain-syntax">, </span><span class="constant-syntax">TEXT_LITERAL_HL</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Task::wraps_existing_storyfile</span><span class="plain-syntax">()) {</span>
<span class="plain-syntax"> </span><a href="2-emt.html#SP7" class="function-link"><span class="function-syntax">Emit::text_constant_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">content_iname</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"--"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">TEMPORARY_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">TLT</span><span class="plain-syntax">)</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">options</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CT_DEQUOTE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="4-tl.html#SP3" class="function-link"><span class="function-syntax">TextLiterals::suppressing_on</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">) == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">unesc</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">options</span><span class="plain-syntax"> += </span><span class="identifier-syntax">CT_EXPAND_APOSTROPHES</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="6-bd.html#SP1" class="function-link"><span class="function-syntax">RTBibliographicData::in_bibliographic_mode</span></a><span class="plain-syntax">()) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">options</span><span class="plain-syntax"> += </span><span class="identifier-syntax">CT_RECOGNISE_APOSTROPHE_SUBSTITUTION</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">options</span><span class="plain-syntax"> += </span><span class="identifier-syntax">CT_RECOGNISE_UNICODE_SUBSTITUTION</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">TranscodeText::from_wide_string</span><span class="plain-syntax">(</span><span class="identifier-syntax">TLT</span><span class="plain-syntax">, </span><span class="identifier-syntax">Lexer::word_text</span><span class="plain-syntax">(</span><span class="identifier-syntax">w1</span><span class="plain-syntax">), </span><span class="identifier-syntax">options</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-emt.html#SP7" class="function-link"><span class="function-syntax">Emit::text_constant_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">content_iname</span><span class="plain-syntax">, </span><span class="identifier-syntax">TLT</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">DISCARD_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">TLT</span><span class="plain-syntax">)</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="4-tl.html#SP1" class="function-link"><span class="function-syntax">TextLiterals::small_block</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">content_iname</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
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