From 29ea4578e46db60b8221e43a802f31982c437016 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Patrick=20L=C3=BChne?= <patrick@luehne.de>
Date: Fri, 27 Mar 2020 03:00:09 +0100
Subject: [PATCH] Move boolean parser to separate module

---
 src/parse.rs          |  2 ++
 src/parse/formulas.rs | 62 ++++----------------------------------
 src/parse/literals.rs | 69 +++++++++++++++++++++++++++++++++++++++++++
 src/parse/terms.rs    | 61 ++++----------------------------------
 4 files changed, 83 insertions(+), 111 deletions(-)
 create mode 100644 src/parse/literals.rs

diff --git a/src/parse.rs b/src/parse.rs
index 9026b2e..1fc7eea 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -1,9 +1,11 @@
 mod formulas;
 mod helpers;
+mod literals;
 mod names;
 mod terms;
 
 pub(crate) use helpers::word_boundary;
+pub(crate) use literals::boolean;
 pub use names::{function_or_predicate_name, variable_name};
 pub use terms::term;
 pub use formulas::formula;
diff --git a/src/parse/formulas.rs b/src/parse/formulas.rs
index eb8f9f2..2966ed4 100644
--- a/src/parse/formulas.rs
+++ b/src/parse/formulas.rs
@@ -9,43 +9,7 @@ use nom::
 	sequence::{delimited, pair, preceded, terminated, tuple},
 };
 
-use super::{Declarations, word_boundary};
-
-// TODO: avoid code duplication
-fn true_(i: &str) -> IResult<&str, crate::Formula>
-{
-	map
-	(
-		terminated
-		(
-			tag("true"),
-			word_boundary,
-		),
-		|_| crate::Formula::true_(),
-	)(i)
-}
-
-fn false_(i: &str) -> IResult<&str, crate::Formula>
-{
-	map
-	(
-		terminated
-		(
-			tag("false"),
-			word_boundary,
-		),
-		|_| crate::Formula::false_(),
-	)(i)
-}
-
-pub fn boolean(i: &str) -> IResult<&str, crate::Formula>
-{
-	alt
-	((
-		true_,
-		false_,
-	))(i)
-}
+use super::{Declarations, boolean, word_boundary};
 
 pub fn predicate<'i>(i: &'i str, d: &Declarations) -> IResult<&'i str, crate::Predicate>
 {
@@ -394,7 +358,11 @@ fn formula_precedence_0<'a>(i: &'a str, d: &Declarations) -> IResult<&'a str, cr
 {
 	alt
 	((
-		boolean,
+		map
+		(
+			boolean,
+			crate::Formula::Boolean,
+		),
 		map
 		(
 			|i| predicate(i, d),
@@ -513,24 +481,6 @@ mod tests
 		assert_eq!(formula("false"), Formula::false_());
 	}*/
 
-	#[test]
-	fn parse_boolean()
-	{
-		assert_eq!(boolean("true"), Ok(("", Formula::true_())));
-		assert_eq!(boolean("false"), Ok(("", Formula::false_())));
-		assert_eq!(boolean("true false"), Ok((" false", Formula::true_())));
-		assert_eq!(boolean("false true"), Ok((" true", Formula::false_())));
-		assert_eq!(boolean("true,"), Ok((",", Formula::true_())));
-		assert_eq!(boolean("false,"), Ok((",", Formula::false_())));
-		assert!(boolean("truefalse").is_err());
-		assert!(boolean("falsetrue").is_err());
-		assert!(boolean("truea").is_err());
-		assert!(boolean("falsea").is_err());
-		assert!(boolean("a").is_err());
-		assert!(boolean("-").is_err());
-		assert!(boolean(" ").is_err());
-	}
-
 	#[test]
 	fn parse_predicate()
 	{
diff --git a/src/parse/literals.rs b/src/parse/literals.rs
new file mode 100644
index 0000000..ca7c084
--- /dev/null
+++ b/src/parse/literals.rs
@@ -0,0 +1,69 @@
+use nom::
+{
+	IResult,
+	branch::alt,
+	bytes::complete::tag,
+	combinator::map,
+	sequence::terminated,
+};
+
+use super::word_boundary;
+
+fn true_(i: &str) -> IResult<&str, bool>
+{
+	map
+	(
+		terminated
+		(
+			tag("true"),
+			word_boundary,
+		),
+		|_| true,
+	)(i)
+}
+
+fn false_(i: &str) -> IResult<&str, bool>
+{
+	map
+	(
+		terminated
+		(
+			tag("false"),
+			word_boundary,
+		),
+		|_| false,
+	)(i)
+}
+
+pub fn boolean(i: &str) -> IResult<&str, bool>
+{
+	alt
+	((
+		true_,
+		false_,
+	))(i)
+}
+
+#[cfg(test)]
+mod tests
+{
+	use crate::parse::*;
+
+	#[test]
+	fn parse_boolean()
+	{
+		assert_eq!(boolean("true"), Ok(("", true)));
+		assert_eq!(boolean("false"), Ok(("", false)));
+		assert_eq!(boolean("true false"), Ok((" false", true)));
+		assert_eq!(boolean("false true"), Ok((" true", false)));
+		assert_eq!(boolean("true,"), Ok((",", true)));
+		assert_eq!(boolean("false,"), Ok((",", false)));
+		assert!(boolean("truefalse").is_err());
+		assert!(boolean("falsetrue").is_err());
+		assert!(boolean("truea").is_err());
+		assert!(boolean("falsea").is_err());
+		assert!(boolean("a").is_err());
+		assert!(boolean("-").is_err());
+		assert!(boolean(" ").is_err());
+	}
+}
diff --git a/src/parse/terms.rs b/src/parse/terms.rs
index 4a1d18a..77b6fab 100644
--- a/src/parse/terms.rs
+++ b/src/parse/terms.rs
@@ -9,7 +9,7 @@ use nom::
 	sequence::{delimited, pair, preceded, terminated},
 };
 
-use super::{Declarations, function_or_predicate_name, word_boundary, variable_name};
+use super::{Declarations, boolean, function_or_predicate_name, variable_name, word_boundary};
 
 fn negative<'i>(i: &'i str, d: &Declarations) -> IResult<&'i str, crate::Term>
 {
@@ -57,41 +57,6 @@ fn absolute_value<'i>(i: &'i str, d: &Declarations) -> IResult<&'i str, crate::T
 	)(i)
 }
 
-fn true_(i: &str) -> IResult<&str, crate::Term>
-{
-	map
-	(
-		terminated
-		(
-			tag("true"),
-			word_boundary,
-		),
-		|_| crate::Term::true_(),
-	)(i)
-}
-
-fn false_(i: &str) -> IResult<&str, crate::Term>
-{
-	map
-	(
-		terminated
-		(
-			tag("false"),
-			word_boundary,
-		),
-		|_| crate::Term::false_(),
-	)(i)
-}
-
-pub fn boolean(i: &str) -> IResult<&str, crate::Term>
-{
-	alt
-	((
-		true_,
-		false_,
-	))(i)
-}
-
 pub fn integer(i: &str) -> IResult<&str, crate::Term>
 {
 	map
@@ -321,7 +286,11 @@ fn term_precedence_0<'a>(i: &'a str, d: &Declarations) -> IResult<&'a str, crate
 {
 	alt
 	((
-		boolean,
+		map
+		(
+			boolean,
+			crate::Term::Boolean,
+		),
 		special_integer,
 		integer,
 		map
@@ -824,24 +793,6 @@ mod tests
 		assert_eq!(format_term("f( \n a \n + \n b \n , \n c \n + \n d \n)"), "f(a + b, c + d)");
 	}
 
-	#[test]
-	fn parse_boolean()
-	{
-		assert_eq!(boolean("true"), Ok(("", Term::true_())));
-		assert_eq!(boolean("false"), Ok(("", Term::false_())));
-		assert_eq!(boolean("true false"), Ok((" false", Term::true_())));
-		assert_eq!(boolean("false true"), Ok((" true", Term::false_())));
-		assert_eq!(boolean("true,"), Ok((",", Term::true_())));
-		assert_eq!(boolean("false,"), Ok((",", Term::false_())));
-		assert!(boolean("truefalse").is_err());
-		assert!(boolean("falsetrue").is_err());
-		assert!(boolean("truea").is_err());
-		assert!(boolean("falsea").is_err());
-		assert!(boolean("a").is_err());
-		assert!(boolean("-").is_err());
-		assert!(boolean(" ").is_err());
-	}
-
 	#[test]
 	fn parse_integer()
 	{