2019-03-17 14:40:57 +02:00
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
< html >
< head >
< title > 1/ins< / title >
< meta http-equiv = "Content-Type" content = "text/html; charset=utf-8" >
< meta http-equiv = "Content-Language" content = "en-gb" >
< link href = "inweb.css" rel = "stylesheet" rev = "stylesheet" type = "text/css" >
< / head >
< body >
<!-- Weave of '1/cs' generated by 7 -->
< ul class = "crumbs" > < li > < a href = "../webs.html" > ★ < / a > < / li > < li > < a href = "index.html" > indoc 4< / a > < / li > < li > < a href = "index.html#1" > Chapter 1: Setting Up< / a > < / li > < li > < b > Context Symbols< / b > < / li > < / ul > < p class = "purpose" > Provides conditional rendering of text, depending on context.< / p >
< ul class = "toc" > < li > < a href = "#SP1" > § 1. About symbols< / a > < / li > < li > < a href = "#SP2" > § 2. Starting up< / a > < / li > < li > < a href = "#SP3" > § 3. Making and unmaking< / a > < / li > < li > < a href = "#SP4" > § 4. Testing< / a > < / li > < / ul > < hr class = "tocbar" >
< p class = "inwebparagraph" > < a id = "SP1" > < / a > < b > § 1. About symbols. < / b > Documentation is allowed to contain rawtext which varies depending on the
context: on what platform it's being written for, or what format it is
being rendered to, for example. The context is defined by which symbol
names have been defined.
< / p >
< p class = "inwebparagraph" > Symbols are C-like identifiers (alphanumeric or underscored). The symbol has
been declared if and only if it is an existing key for the following hash,
and the associated value is "y".
< / p >
< pre class = "display" >
< span class = "reserved" > dictionary< / span > < span class = "plain" > *< / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > = < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ;< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP2" > < / a > < b > § 2. Starting up. < / b > The symbol < code class = "display" > < span class = "extract" > indoc< / span > < / code > is always defined, so that, in theory, other programs
working on rawtext can distinguish themselves from us (by not defining it).
For example,
< / p >
< p class = "inwebparagraph" > < / p >
< pre class = "display" >
< span class = "plain" > {^indoc:}You'll probably never see this paragraph.< / span >
< / pre >
< p class = "inwebparagraph" > provides rawtext visible only if < code class = "display" > < span class = "extract" > indoc< / span > < / code > isn't the renderer.
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::start_up_symbols< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > ) {< / span >
< span class = "functiontext" > Symbols::declare_symbol< / span > < span class = "plain" > (< / span > < span class = "identifier" > I< / span > < span class = "string" > "indoc"< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Symbols::start_up_symbols is used in 1/mn (< a href = "1-mn.html#SP1_1" > § 1.1< / a > ).< / p >
< p class = "inwebparagraph" > < a id = "SP3" > < / a > < b > § 3. Making and unmaking. < / b > < / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::declare_symbol< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > symbol< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ) < / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Dictionaries::new< / span > < span class = "plain" > (10, < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > entry< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Dictionaries::create_text< / span > < span class = "plain" > (< / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > , < / span > < span class = "identifier" > symbol< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::copy< / span > < span class = "plain" > (< / span > < span class = "identifier" > entry< / span > < span class = "plain" > , < / span > < span class = "identifier" > I< / span > < span class = "string" > "y"< / span > < span class = "plain" > );< / span >
< span class = "identifier" > LOGIF< / span > < span class = "plain" > (< / span > < span class = "identifier" > SYMBOLS< / span > < span class = "plain" > , < / span > < span class = "string" > "Declaring < %S> \< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > symbol< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::undeclare_symbol< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > symbol< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > entry< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Dictionaries::get_text< / span > < span class = "plain" > (< / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > , < / span > < span class = "identifier" > symbol< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > entry< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > ;< / span >
< span class = "functiontext" > Str::copy< / span > < span class = "plain" > (< / span > < span class = "identifier" > entry< / span > < span class = "plain" > , < / span > < span class = "identifier" > I< / span > < span class = "string" > "n"< / span > < span class = "plain" > );< / span >
< span class = "identifier" > LOGIF< / span > < span class = "plain" > (< / span > < span class = "identifier" > SYMBOLS< / span > < span class = "plain" > , < / span > < span class = "string" > "Undeclaring < %S> \< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > symbol< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Symbols::declare_symbol is used in < a href = "#SP2" > § 2< / a > , 1/ins (< a href = "1-ins.html#SP5" > § 5< / a > , < a href = "1-ins.html#SP3_2" > § 3.2< / a > ).< / p >
< p class = "endnote" > The function Symbols::undeclare_symbol is used in 1/ins (< a href = "1-ins.html#SP5" > § 5< / a > ).< / p >
< p class = "inwebparagraph" > < a id = "SP4" > < / a > < b > § 4. Testing. < / b > This returns 1 if the current context matches the condition given, and 0
otherwise.
< / p >
< pre class = "display" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > cond< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > i< / span > < span class = "plain" > =0, < / span > < span class = "identifier" > L< / span > < span class = "plain" > =< / span > < span class = "functiontext" > Str::len< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > ); < / span > < span class = "identifier" > i< / span > < span class = "plain" > < < / span > < span class = "identifier" > L< / span > < span class = "plain" > ; < / span > < span class = "identifier" > i< / span > < span class = "plain" > ++) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > c< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Str::get_at< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > Characters::is_whitespace< / span > < span class = "plain" > (< / span > < span class = "identifier" > c< / span > < span class = "plain" > )) {< / span >
< span class = "functiontext" > Str::delete_nth_character< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > );< / span >
< span class = "identifier" > i< / span > < span class = "plain" > --; < / span > < span class = "identifier" > L< / span > < span class = "plain" > --;< / span >
< span class = "plain" > }< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > v< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Symbols::perform_ifdef_inner< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > );< / span >
< span class = "identifier" > LOGIF< / span > < span class = "plain" > (< / span > < span class = "identifier" > SYMBOLS< / span > < span class = "plain" > , < / span > < span class = "string" > "Ifdef < %S> --> %s\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > v< / span > < span class = "plain" > ?< / span > < span class = "string" > "yes"< / span > < span class = "plain" > :< / span > < span class = "string" > "no"< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > v< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Symbols::perform_ifdef is used in < a href = "#SP5_1" > § 5.1< / a > , < a href = "#SP5_2" > § 5.2< / a > , < a href = "#SP5_3" > § 5.3< / a > , < a href = "#SP5_4" > § 5.4< / a > , 2/ss (< a href = "2-ss.html#SP6_1" > § 6.1< / a > ), 2/rr (< a href = "2-rr.html#SP4_1" > § 4.1< / a > , < a href = "2-rr.html#SP4_6_1" > § 4.6.1< / a > ).< / p >
< p class = "inwebparagraph" > < a id = "SP5" > < / a > < b > § 5. < / b > There is an expression grammar here, which we apply correctly if the
condition is well-formed; if it"s a mess, we try to return 0, but don"t go
to any trouble to report errors.
< / p >
< p class = "inwebparagraph" > Any condition can be bracketed; otherwise we have the unary operator < code class = "display" > < span class = "extract" > ^< / span > < / code >
(negation), the binary < code class = "display" > < span class = "extract" > +< / span > < / code > (conjunction), and binary < code class = "display" > < span class = "extract" > ,< / span > < / code > (disjunction),
which associate in that order. An atomic condition is true if and only if
it is a declared symbol. So for example
< / p >
< p class = "inwebparagraph" > ^alpha,beta+gamma
< / p >
< p class = "inwebparagraph" > is true if either alpha is undeclared, or if both beta and gamma are declared.
Whereas
< / p >
< p class = "inwebparagraph" > ^(alpha,beta)+gamma
^alpha+^beta+gamma
< / p >
< p class = "inwebparagraph" > are both true if alpha and beta are undeclared but gamma is declared.
< / p >
< pre class = "display" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::perform_ifdef_inner< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > cond< / span > < span class = "plain" > ) {< / span >
< < span class = "cwebmacro" > Subexpressions can be bracketed< / span > < span class = "cwebmacronumber" > 5.1< / span > > < span class = "plain" > ;< / span >
< < span class = "cwebmacro" > The comma operator is left-associative and means or< / span > < span class = "cwebmacronumber" > 5.2< / span > > < span class = "plain" > ;< / span >
< < span class = "cwebmacro" > The plus operator is left-associative and means and< / span > < span class = "cwebmacronumber" > 5.3< / span > > < span class = "plain" > ;< / span >
< < span class = "cwebmacro" > The caret operator is unary and means not< / span > < span class = "cwebmacronumber" > 5.4< / span > > < span class = "plain" > ;< / span >
< < span class = "cwebmacro" > A bare symbol name is true if and only if it is declared< / span > < span class = "cwebmacronumber" > 5.5< / span > > < span class = "plain" > ;< / span >
< < span class = "cwebmacro" > The expression is malformed< / span > < span class = "cwebmacronumber" > 5.6< / span > > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Symbols::perform_ifdef_inner is used in < a href = "#SP4" > § 4< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_1" > < / a > < b > § 5.1. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > Subexpressions can be bracketed< / span > < span class = "cwebmacronumber" > 5.1< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "reserved" > match_results< / span > < span class = "plain" > < / span > < span class = "identifier" > mr< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Regexp::create_mr< / span > < span class = "plain" > ();< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > Regexp::match< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > L< / span > < span class = "string" > "%((%c*)%)"< / span > < span class = "plain" > )) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > mr< / span > < span class = "element" > .exp< / span > < span class = "plain" > [0]);< / span >
< span class = "functiontext" > Regexp::dispose_of< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_2" > < / a > < b > § 5.2. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > The comma operator is left-associative and means or< / span > < span class = "cwebmacronumber" > 5.2< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > k< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Symbols::find_operator< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "character" > ','< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > k< / span > < span class = "plain" > > = 0) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > );< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::copy< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::truncate< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > , < / span > < span class = "identifier" > k< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::copy_tail< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > k< / span > < span class = "plain" > +1);< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = ((< / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > )) || (< / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > )));< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > ;< / span >
< span class = "plain" > } < / span > < span class = "reserved" > else< / span > < span class = "plain" > < / span > < span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > k< / span > < span class = "plain" > == -2) < / span > < < span class = "cwebmacro" > The expression is malformed< / span > < span class = "cwebmacronumber" > 5.6< / span > > < span class = "plain" > ;< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_3" > < / a > < b > § 5.3. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > The plus operator is left-associative and means and< / span > < span class = "cwebmacronumber" > 5.3< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > k< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Symbols::find_operator< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "character" > '+'< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > k< / span > < span class = "plain" > > = 0) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > );< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::copy< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::truncate< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > , < / span > < span class = "identifier" > k< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Str::copy_tail< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > k< / span > < span class = "plain" > +1);< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = ((< / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > )) & & (< / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > )));< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > L< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > R< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > ;< / span >
< span class = "plain" > } < / span > < span class = "reserved" > else< / span > < span class = "plain" > < / span > < span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > k< / span > < span class = "plain" > == -2) < / span > < < span class = "cwebmacro" > The expression is malformed< / span > < span class = "cwebmacronumber" > 5.6< / span > > < span class = "plain" > ;< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_4" > < / a > < b > § 5.4. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > The caret operator is unary and means not< / span > < span class = "cwebmacronumber" > 5.4< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "reserved" > match_results< / span > < span class = "plain" > < / span > < span class = "identifier" > mr< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Regexp::create_mr< / span > < span class = "plain" > ();< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > Regexp::match< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > L< / span > < span class = "string" > "%^(%c*)"< / span > < span class = "plain" > )) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Symbols::perform_ifdef< / span > < span class = "plain" > (< / span > < span class = "identifier" > mr< / span > < span class = "element" > .exp< / span > < span class = "plain" > [0]);< / span >
< span class = "functiontext" > Regexp::dispose_of< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > ?< / span > < span class = "constant" > FALSE< / span > < span class = "plain" > :< / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_5" > < / a > < b > § 5.5. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > A bare symbol name is true if and only if it is declared< / span > < span class = "cwebmacronumber" > 5.5< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "reserved" > match_results< / span > < span class = "plain" > < / span > < span class = "identifier" > mr< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Regexp::create_mr< / span > < span class = "plain" > ();< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > Regexp::match< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > L< / span > < span class = "string" > "%i+"< / span > < span class = "plain" > )) {< / span >
< span class = "functiontext" > Regexp::dispose_of< / span > < span class = "plain" > (& < / span > < span class = "identifier" > mr< / span > < span class = "plain" > );< / span >
< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > entry< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Dictionaries::get_text< / span > < span class = "plain" > (< / span > < span class = "identifier" > defined_symbols< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > Str::eq_wide_string< / span > < span class = "plain" > (< / span > < span class = "identifier" > entry< / span > < span class = "plain" > , < / span > < span class = "identifier" > L< / span > < span class = "string" > "y"< / span > < span class = "plain" > )) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5_6" > < / a > < b > § 5.6. < / b > < code class = "display" >
< < span class = "cwebmacrodefn" > The expression is malformed< / span > < span class = "cwebmacronumber" > 5.6< / span > > =
< / code > < / p >
< pre class = "displaydefn" >
< span class = "functiontext" > Errors::with_text< / span > < span class = "plain" > (< / span > < span class = "string" > "malformed condition: %S"< / span > < span class = "plain" > , < / span > < span class = "identifier" > cond< / span > < span class = "plain" > ); < / span > < span class = "reserved" > return< / span > < span class = "plain" > 0;< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > This code is used in < a href = "#SP5" > § 5< / a > , < a href = "#SP5_2" > § 5.2< / a > , < a href = "#SP5_3" > § 5.3< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP6" > < / a > < b > § 6. < / b > The following looks for a single character < code class = "display" > < span class = "extract" > op< / span > < / code > in any unbracketed interior
parts of the text < code class = "display" > < span class = "extract" > cond< / span > < / code > , and looks out for mismatched brackets on the way.
< / p >
< pre class = "display" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "functiontext" > Symbols::find_operator< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > op< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > bl< / span > < span class = "plain" > = 0;< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > k< / span > < span class = "plain" > = 0, < / span > < span class = "identifier" > L< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Str::len< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > ); < / span > < span class = "identifier" > k< / span > < span class = "plain" > < < / span > < span class = "identifier" > L< / span > < span class = "plain" > ; < / span > < span class = "identifier" > k< / span > < span class = "plain" > ++) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > ch< / span > < span class = "plain" > = < / span > < span class = "functiontext" > Str::get_at< / span > < span class = "plain" > (< / span > < span class = "identifier" > cond< / span > < span class = "plain" > , < / span > < span class = "identifier" > k< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > ch< / span > < span class = "plain" > == < / span > < span class = "character" > '('< / span > < span class = "plain" > ) < / span > < span class = "identifier" > bl< / span > < span class = "plain" > ++;< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > ch< / span > < span class = "plain" > == < / span > < span class = "character" > ')'< / span > < span class = "plain" > ) < / span > < span class = "identifier" > bl< / span > < span class = "plain" > --;< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > bl< / span > < span class = "plain" > < 0) < / span > < span class = "reserved" > return< / span > < span class = "plain" > -2; < / span > < span class = "comment" > Too many close brackets< / span >
< span class = "reserved" > if< / span > < span class = "plain" > ((< / span > < span class = "identifier" > bl< / span > < span class = "plain" > == 0) & & (< / span > < span class = "identifier" > k< / span > < span class = "plain" > > 0) & & (< / span > < span class = "identifier" > k< / span > < span class = "plain" > < < / span > < span class = "identifier" > L< / span > < span class = "plain" > - 1) & & (< / span > < span class = "identifier" > ch< / span > < span class = "plain" > == < / span > < span class = "identifier" > op< / span > < span class = "plain" > )) {< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > k< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > bl< / span > < span class = "plain" > != 0) < / span > < span class = "reserved" > return< / span > < span class = "plain" > -2; < / span > < span class = "comment" > Too many open brackets< / span >
< span class = "reserved" > return< / span > < span class = "plain" > -1; < / span > < span class = "comment" > Not found< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Symbols::find_operator is used in < a href = "#SP5_2" > § 5.2< / a > , < a href = "#SP5_3" > § 5.3< / a > .< / p >
< hr class = "tocbar" >
< ul class = "toc" > < li > < a href = "1-ins.html" > Back to 'Instructions'< / a > < / li > < li > < i > (This section ends Chapter 1: Setting Up.)< / i > < / li > < / ul > < hr class = "tocbar" >
2019-04-22 17:42:10 +03:00
<!-- End of weave -->
2019-03-17 14:40:57 +02:00
< / body >
< / html >