Merge pull request #5355 from dsbos/dsbos-SpecEdits

Italicize more defining occurrences of terms in Scala lang. spec.

7 files changed, 54 insertions, 54 deletions

diff --git a/spec/03-types.md b/spec/03-types.md
index e2a6523dff..2ad16e50cb 100644
--- a/spec/03-types.md
+++ b/spec/03-types.md
@@ -105,7 +105,7 @@ forms.
 SimpleType  ::=  Path ‘.’ type
 ```
 
-A singleton type is of the form $p.$`type`, where $p$ is a
+A _singleton type_ is of the form $p.$`type`, where $p$ is a
 path pointing to a value expected to [conform](06-expressions.html#expression-typing)
 to `scala.AnyRef`. The type denotes the set of values
 consisting of `null` and the value denoted by $p$.
@@ -119,7 +119,7 @@ declared to be a subtype of trait `scala.Singleton`.
 SimpleType  ::=  SimpleType ‘#’ id
 ```
 
-A type projection $T$#$x$ references the type member named
+A _type projection_ $T$#$x$ references the type member named
 $x$ of type $T$.
 
 <!--
@@ -134,7 +134,7 @@ If $x$ references an abstract type member, then $T$ must be a
 SimpleType  ::=  StableId
 ```
 
-A type designator refers to a named value type. It can be simple or
+A _type designator_ refers to a named value type. It can be simple or
 qualified. All such type designators are shorthands for type projections.
 
 Specifically, the unqualified type name $t$ where $t$ is bound in some
@@ -167,7 +167,7 @@ SimpleType      ::=  SimpleType TypeArgs
 TypeArgs        ::=  ‘[’ Types ‘]’
 ```
 
-A parameterized type $T[ T_1 , \ldots , T_n ]$ consists of a type
+A _parameterized type_ $T[ T_1 , \ldots , T_n ]$ consists of a type
 designator $T$ and type parameters $T_1 , \ldots , T_n$ where
 $n \geq 1$. $T$ must refer to a type constructor which takes $n$ type
 parameters $a_1 , \ldots , a_n$.
@@ -227,7 +227,7 @@ G[S, Int]             // illegal: S constrains its parameter to
 SimpleType    ::=   ‘(’ Types ‘)’
 ```
 
-A tuple type $(T_1 , \ldots , T_n)$ is an alias for the
+A _tuple type_ $(T_1 , \ldots , T_n)$ is an alias for the
 class `scala.Tuple$n$[$T_1$, … , $T_n$]`, where $n \geq 2$.
 
 Tuple classes are case classes whose fields can be accessed using
@@ -255,7 +255,7 @@ trait Product_n[+$T_1$, … , +$T_n$] {
 AnnotType  ::=  SimpleType {Annotation}
 ```
 
-An annotated type $T$ $a_1, \ldots, a_n$
+An _annotated type_ $T$ $a_1, \ldots, a_n$
 attaches [annotations](11-annotations.html#user-defined-annotations)
 $a_1 , \ldots , a_n$ to the type $T$.
 
@@ -278,7 +278,7 @@ RefineStat      ::=  Dcl
                   |
 ```
 
-A compound type $T_1$ `with` … `with` $T_n \\{ R \\}$
+A _compound type_ $T_1$ `with` … `with` $T_n \\{ R \\}$
 represents objects with members as given in the component types
 $T_1 , \ldots , T_n$ and the refinement $\\{ R \\}$. A refinement
 $\\{ R \\}$ contains declarations and type definitions.
@@ -343,7 +343,7 @@ a value `callsign` and a `fly` method.
 InfixType     ::=  CompoundType {id [nl] CompoundType}
 ```
 
-An infix type $T_1$ `op` $T_2$ consists of an infix
+An _infix type_ $T_1$ `op` $T_2$ consists of an infix
 operator `op` which gets applied to two type operands $T_1$ and
 $T_2$.  The type is equivalent to the type application
 `op`$[T_1, T_2]$.  The infix operator `op` may be an
@@ -410,7 +410,7 @@ ExistentialDcl     ::= ‘type’ TypeDcl
                     |  ‘val’ ValDcl
 ```
 
-An existential type has the form `$T$ forSome { $Q$ }`
+An _existential type_ has the form `$T$ forSome { $Q$ }`
 where $Q$ is a sequence of
 [type declarations](04-basic-declarations-and-definitions.html#type-declarations-and-type-aliases).
 
@@ -564,7 +564,7 @@ report as the internal types of defined identifiers.
 
 ### Method Types
 
-A method type is denoted internally as $(\mathit{Ps})U$, where $(\mathit{Ps})$
+A _method type_ is denoted internally as $(\mathit{Ps})U$, where $(\mathit{Ps})$
 is a sequence of parameter names and types $(p_1:T_1 , \ldots , p_n:T_n)$
 for some $n \geq 0$ and $U$ is a (value or method) type.  This type
 represents named methods that take arguments named $p_1 , \ldots , p_n$
@@ -631,7 +631,7 @@ union : [A >: Nothing <: Comparable[A]] (x: Set[A], xs: Set[A]) Set[A]
 
 ### Type Constructors
 
-A type constructor is represented internally much like a polymorphic method type.
+A _type constructor_ is represented internally much like a polymorphic method type.
 `[$\pm$ $a_1$ >: $L_1$ <: $U_1 , \ldots , \pm a_n$ >: $L_n$ <: $U_n$] $T$`
 represents a type that is expected by a
 [type constructor parameter](04-basic-declarations-and-definitions.html#type-parameters) or an
diff --git a/spec/04-basic-declarations-and-definitions.md b/spec/04-basic-declarations-and-definitions.md
index 7790428ca8..f6068eb9d8 100644
--- a/spec/04-basic-declarations-and-definitions.md
+++ b/spec/04-basic-declarations-and-definitions.md
@@ -595,9 +595,9 @@ ParamType          ::=  Type
                      |  Type ‘*’
 ```
 
-A function declaration has the form `def $f\,\mathit{psig}$: $T$`, where
+A _function declaration_ has the form `def $f\,\mathit{psig}$: $T$`, where
 $f$ is the function's name, $\mathit{psig}$ is its parameter
-signature and $T$ is its result type. A function definition
+signature and $T$ is its result type. A _function definition_
 `def $f\,\mathit{psig}$: $T$ = $e$` also includes a _function body_ $e$,
 i.e. an expression which defines the function's result.  A parameter
 signature consists of an optional type parameter clause `[$\mathit{tps}\,$]`,
@@ -612,13 +612,13 @@ result type, if one is given. If the function definition is not
 recursive, the result type may be omitted, in which case it is
 determined from the packed type of the function body.
 
-A type parameter clause $\mathit{tps}$ consists of one or more
+A _type parameter clause_ $\mathit{tps}$ consists of one or more
 [type declarations](#type-declarations-and-type-aliases), which introduce type
 parameters, possibly with bounds.  The scope of a type parameter includes
 the whole signature, including any of the type parameter bounds as
 well as the function body, if it is present.
 
-A value parameter clause $\mathit{ps}$ consists of zero or more formal
+A _value parameter clause_ $\mathit{ps}$ consists of zero or more formal
 parameter bindings such as `$x$: $T$` or `$x: T = e$`, which bind value
 parameters and associate them with their types.
 
@@ -774,12 +774,12 @@ FunDef   ::=  FunSig [nl] ‘{’ Block ‘}’
 
 Special syntax exists for procedures, i.e. functions that return the
 `Unit` value `()`.
-A procedure declaration is a function declaration where the result type
+A _procedure declaration_ is a function declaration where the result type
 is omitted. The result type is then implicitly completed to the
 `Unit` type. E.g., `def $f$($\mathit{ps}$)` is equivalent to
 `def $f$($\mathit{ps}$): Unit`.
 
-A procedure definition is a function definition where the result type
+A _procedure definition_ is a function definition where the result type
 and the equals sign are omitted; its defining expression must be a block.
 E.g., `def $f$($\mathit{ps}$) {$\mathit{stats}$}` is equivalent to
 `def $f$($\mathit{ps}$): Unit = {$\mathit{stats}$}`.
diff --git a/spec/05-classes-and-objects.md b/spec/05-classes-and-objects.md
index f92e88788a..d1a1a8739d 100644
--- a/spec/05-classes-and-objects.md
+++ b/spec/05-classes-and-objects.md
@@ -27,7 +27,7 @@ SelfType        ::=  id [`:' Type] `=>'
                  |   this `:' Type `=>'
 ```
 
-A template defines the type signature, behavior and initial state of a
+A _template_ defines the type signature, behavior and initial state of a
 trait or class of objects or of a single object. Templates form part of
 instance creation expressions, class definitions, and object
 definitions.  A template
@@ -972,7 +972,7 @@ TraitDef         ::=  id [TypeParamClause] TraitTemplateOpt
 TraitTemplateOpt ::=  `extends' TraitTemplate | [[`extends'] TemplateBody]
 ```
 
-A trait is a class that is meant to be added to some other class
+A _trait_ is a class that is meant to be added to some other class
 as a mixin. Unlike normal classes, traits cannot have
 constructor parameters. Furthermore, no constructor arguments are
 passed to the superclass of the trait. This is not necessary as traits are
@@ -1074,7 +1074,7 @@ in `MyTable`.
 ObjectDef       ::=  id ClassTemplate
 ```
 
-An object definition defines a single object of a new class. Its
+An _object definition_ defines a single object of a new class. Its
 most general form is
 `object $m$ extends $t$`. Here,
 $m$ is the name of the object to be defined, and
diff --git a/spec/06-expressions.md b/spec/06-expressions.md
index 1ecba5adf1..9df9249373 100644
--- a/spec/06-expressions.md
+++ b/spec/06-expressions.md
@@ -436,7 +436,7 @@ because otherwise the underscore would be considered part of the name.
 SimpleExpr    ::=  SimpleExpr TypeArgs
 ```
 
-A type application `$e$[$T_1 , \ldots , T_n$]` instantiates
+A _type application_ `$e$[$T_1 , \ldots , T_n$]` instantiates
 a polymorphic value $e$ of type
 `[$a_1$ >: $L_1$ <: $U_1, \ldots , a_n$ >: $L_n$ <: $U_n$]$S$`
 with argument types
@@ -462,7 +462,7 @@ and the expected result type.
 SimpleExpr   ::=  `(' [Exprs] `)'
 ```
 
-A tuple expression `($e_1 , \ldots , e_n$)` is an alias
+A _tuple expression_ `($e_1 , \ldots , e_n$)` is an alias
 for the class instance creation
 `scala.Tuple$n$($e_1 , \ldots , e_n$)`, where $n \geq 2$.
 The empty tuple
@@ -474,7 +474,7 @@ The empty tuple
 SimpleExpr     ::=  `new' (ClassTemplate | TemplateBody)
 ```
 
-A simple instance creation expression is of the form
+A _simple instance creation expression_ is of the form
 `new $c$`
 where $c$ is a [constructor invocation](05-classes-and-objects.html#constructor-invocations). Let $T$ be
 the type of $c$. Then $T$ must
@@ -497,7 +497,7 @@ The expression is evaluated by creating a fresh
 object of type $T$ which is initialized by evaluating $c$. The
 type of the expression is $T$.
 
-A general instance creation expression is of the form
+A _general instance creation expression_ is of the form
 `new $t$` for some [class template](05-classes-and-objects.html#templates) $t$.
 Such an expression is equivalent to the block
 
@@ -542,7 +542,7 @@ BlockExpr  ::=  ‘{’ CaseClauses ‘}’
 Block      ::=  BlockStat {semi BlockStat} [ResultExpr]
 ```
 
-A block expression `{$s_1$; $\ldots$; $s_n$; $e\,$}` is
+A _block expression_ `{$s_1$; $\ldots$; $s_n$; $e\,$}` is
 constructed from a sequence of block statements $s_1 , \ldots , s_n$
 and a final expression $e$.  The statement sequence may not contain
 two definitions or declarations that bind the same name in the same
@@ -697,7 +697,7 @@ name.
 
 ### Assignment Operators
 
-An assignment operator is an operator symbol (syntax category
+An _assignment operator_ is an operator symbol (syntax category
 `op` in [Identifiers](01-lexical-syntax.html#identifiers)) that ends in an equals character
 “`=`”, with the exception of operators for which one of
 the following conditions holds:
@@ -736,7 +736,7 @@ The re-interpretation occurs if the following two conditions are fulfilled.
 Expr1              ::=  PostfixExpr `:' CompoundType
 ```
 
-The typed expression $e: T$ has type $T$. The type of
+The _typed expression_ $e: T$ has type $T$. The type of
 expression $e$ is expected to conform to $T$. The result of
 the expression is the value of $e$ converted to type $T$.
 
@@ -755,7 +755,7 @@ Here are examples of well-typed and ill-typed expressions.
 Expr1              ::=  PostfixExpr `:' Annotation {Annotation}
 ```
 
-An annotated expression `$e$: @$a_1$ $\ldots$ @$a_n$`
+An _annotated expression_ `$e$: @$a_1$ $\ldots$ @$a_n$`
 attaches [annotations](11-annotations.html#user-defined-annotations) $a_1 , \ldots , a_n$ to the
 expression $e$.
 
@@ -850,7 +850,7 @@ def matmul(xss: Array[Array[Double]], yss: Array[Array[Double]]) = {
 Expr1          ::=  `if' `(' Expr `)' {nl} Expr [[semi] `else' Expr]
 ```
 
-The conditional expression `if ($e_1$) $e_2$ else $e_3$` chooses
+The _conditional expression_ `if ($e_1$) $e_2$ else $e_3$` chooses
 one of the values of $e_2$ and $e_3$, depending on the
 value of $e_1$. The condition $e_1$ is expected to
 conform to type `Boolean`.  The then-part $e_2$ and the
@@ -876,7 +876,7 @@ evaluated as if it was `if ($e_1$) $e_2$ else ()`.
 Expr1          ::=  `while' `(' Expr ')' {nl} Expr
 ```
 
-The while loop expression `while ($e_1$) $e_2$` is typed and
+The _while loop expression_ `while ($e_1$) $e_2$` is typed and
 evaluated as if it was an application of `whileLoop ($e_1$) ($e_2$)` where
 the hypothetical function `whileLoop` is defined as follows.
 
@@ -891,7 +891,7 @@ def whileLoop(cond: => Boolean)(body: => Unit): Unit  =
 Expr1          ::=  `do' Expr [semi] `while' `(' Expr ')'
 ```
 
-The do loop expression `do $e_1$ while ($e_2$)` is typed and
+The _do loop expression_ `do $e_1$ while ($e_2$)` is typed and
 evaluated as if it was the expression `($e_1$ ; while ($e_2$) $e_1$)`.
 A semicolon preceding the `while` symbol of a do loop expression is ignored.
 
@@ -905,9 +905,9 @@ Generator      ::=  Pattern1 `<-' Expr {[semi] Guard | semi Pattern1 `=' Expr}
 Guard          ::=  `if' PostfixExpr
 ```
 
-A for loop `for ($\mathit{enums}\,$) $e$` executes expression $e$
-for each binding generated by the enumerators $\mathit{enums}$.  A for
-comprehension `for ($\mathit{enums}\,$) yield $e$` evaluates
+A _for loop_ `for ($\mathit{enums}\,$) $e$` executes expression $e$
+for each binding generated by the enumerators $\mathit{enums}$. 
+A _for comprehension_ `for ($\mathit{enums}\,$) yield $e$` evaluates
 expression $e$ for each binding generated by the enumerators $\mathit{enums}$
 and collects the results. An enumerator sequence always starts with a
 generator; this can be followed by further generators, value
@@ -1049,7 +1049,7 @@ The code above makes use of the fact that `map`, `flatMap`,
 Expr1      ::=  `return' [Expr]
 ```
 
-A return expression `return $e$` must occur inside the body of some
+A _return expression_ `return $e$` must occur inside the body of some
 enclosing named method or function. The innermost enclosing named
 method or function in a source program, $f$, must have an explicitly declared result type,
 and the type of $e$ must conform to it.
@@ -1086,7 +1086,7 @@ and will propagate up the call stack.
 Expr1      ::=  `throw' Expr
 ```
 
-A throw expression `throw $e$` evaluates the expression
+A _throw expression_ `throw $e$` evaluates the expression
 $e$. The type of this expression must conform to
 `Throwable`.  If $e$ evaluates to an exception
 reference, evaluation is aborted with the thrown exception. If $e$
@@ -1104,7 +1104,7 @@ Expr1 ::=  `try' (`{' Block `}' | Expr) [`catch' `{' CaseClauses `}']
            [`finally' Expr]
 ```
 
-A try expression is of the form `try { $b$ } catch $h$`
+A _try expression_ is of the form `try { $b$ } catch $h$`
 where the handler $h$ is a
 [pattern matching anonymous function](08-pattern-matching.html#pattern-matching-anonymous-functions)
 
@@ -1278,7 +1278,7 @@ TemplateStat ::=  Import
                |
 ```
 
-Statements occur as parts of blocks and templates.  A statement can be
+Statements occur as parts of blocks and templates.  A _statement_ can be
 an import, a definition or an expression, or it can be empty.
 Statements used in the template of a class definition can also be
 declarations.  An expression that is used as a statement can have an
diff --git a/spec/07-implicits.md b/spec/07-implicits.md
index 28f6dfe5a8..662b653f71 100644
--- a/spec/07-implicits.md
+++ b/spec/07-implicits.md
@@ -44,7 +44,7 @@ object Monoids {
 
 ## Implicit Parameters
 
-An implicit parameter list
+An _implicit parameter list_
 `(implicit $p_1$,$\ldots$,$p_n$)` of a method marks the parameters $p_1 , \ldots , p_n$ as
 implicit. A method or constructor can have only one implicit parameter
 list, and it must be the last parameter list given.
diff --git a/spec/08-pattern-matching.md b/spec/08-pattern-matching.md
index 35eb97b948..00f9099bea 100644
--- a/spec/08-pattern-matching.md
+++ b/spec/08-pattern-matching.md
@@ -60,7 +60,7 @@ patterns.
                     |  varid
 ```
 
-A variable pattern $x$ is a simple identifier which starts with a
+A _variable pattern_ $x$ is a simple identifier which starts with a
 lower case letter.  It matches any value, and binds the variable name
 to that value.  The type of $x$ is the expected type of the pattern as
 given from outside.  A special case is the wild-card pattern `_`
@@ -73,7 +73,7 @@ which is treated as if it was a fresh variable on each occurrence.
                     |  `_' `:' TypePat
 ```
 
-A typed pattern $x: T$ consists of a pattern variable $x$ and a
+A _typed pattern_ $x: T$ consists of a pattern variable $x$ and a
 type pattern $T$.  The type of $x$ is the type pattern $T$, where
 each type variable and wildcard is replaced by a fresh, unknown type.
 This pattern matches any value matched by the [type pattern](#type-patterns)
@@ -86,7 +86,7 @@ that value.
   Pattern2        ::=  varid `@' Pattern3
 ```
 
-A pattern binder `$x$@$p$` consists of a pattern variable $x$ and a
+A _pattern binder_ `$x$@$p$` consists of a pattern variable $x$ and a
 pattern $p$. The type of the variable $x$ is the static type $T$ of the pattern $p$.
 This pattern matches any value $v$ matched by the pattern $p$,
 provided the run-time type of $v$ is also an instance of $T$,
@@ -98,7 +98,7 @@ and it binds the variable name to that value.
   SimplePattern   ::=  Literal
 ```
 
-A literal pattern $L$ matches any value that is equal (in terms of
+A _literal pattern_ $L$ matches any value that is equal (in terms of
 `==`) to the literal $L$. The type of $L$ must conform to the
 expected type of the pattern.
 
@@ -108,7 +108,7 @@ expected type of the pattern.
   SimplePattern   ::=  StableId
 ```
 
-A stable identifier pattern is a [stable identifier](03-types.html#paths) $r$.
+A _stable identifier pattern_ is a [stable identifier](03-types.html#paths) $r$.
 The type of $r$ must conform to the expected
 type of the pattern. The pattern matches any value $v$ such that
 `$r$ == $v$` (see [here](12-the-scala-standard-library.html#root-classes)).
@@ -147,7 +147,7 @@ argument of `f` are equal.
 SimplePattern   ::=  StableId `(' [Patterns] `)
 ```
 
-A constructor pattern is of the form $c(p_1 , \ldots , p_n)$ where $n
+A _constructor pattern_ is of the form $c(p_1 , \ldots , p_n)$ where $n
 \geq 0$. It consists of a stable identifier $c$, followed by element
 patterns $p_1 , \ldots , p_n$. The constructor $c$ is a simple or
 qualified name which denotes a [case class](05-classes-and-objects.html#case-classes).
@@ -173,7 +173,7 @@ repeated parameter. This is further discussed [here](#pattern-sequences).
   SimplePattern   ::=  `(' [Patterns] `)'
 ```
 
-A tuple pattern `($p_1 , \ldots , p_n$)` is an alias
+A _tuple pattern_ `($p_1 , \ldots , p_n$)` is an alias
 for the constructor pattern `scala.Tuple$n$($p_1 , \ldots , p_n$)`,
 where $n \geq 2$. The empty tuple
 `()` is the unique value of type `scala.Unit`.
@@ -184,7 +184,7 @@ where $n \geq 2$. The empty tuple
   SimplePattern   ::=  StableId `(' [Patterns] `)'
 ```
 
-An extractor pattern $x(p_1 , \ldots , p_n)$ where $n \geq 0$ is of
+An _extractor pattern_ $x(p_1 , \ldots , p_n)$ where $n \geq 0$ is of
 the same syntactic form as a constructor pattern. However, instead of
 a case class, the stable identifier $x$ denotes an object which has a
 member method named `unapply` or `unapplySeq` that matches
@@ -244,7 +244,7 @@ val y = x match {
 SimplePattern ::= StableId `(' [Patterns `,'] [varid `@'] `_' `*' `)'
 ```
 
-A pattern sequence $p_1 , \ldots , p_n$ appears in two contexts.
+A _pattern sequence_ $p_1 , \ldots , p_n$ appears in two contexts.
 First, in a constructor pattern $c(q_1 , \ldots , q_m, p_1 , \ldots , p_n)$, where $c$ is a case class which has $m+1$ primary constructor parameters,  ending in a [repeated parameter](04-basic-declarations-and-definitions.html#repeated-parameters) of type `S*`.
 Second, in an extractor pattern $x(q_1 , \ldots , q_m, p_1 , \ldots , p_n)$ if the extractor object $x$ does not have an `unapply` method,
 but it does define an `unapplySeq` method with a result type conforming to `Option[(T_1, ... , T_m, Seq[S])]` (if `m = 0`, the type `Option[Seq[S]]` is also accepted). The expected type for the patterns $p_i$ is $S$.
@@ -265,7 +265,7 @@ p_n$.
   Pattern3  ::=  SimplePattern {id [nl] SimplePattern}
 ```
 
-An infix operation pattern $p;\mathit{op};q$ is a shorthand for the
+An _infix operation pattern_ $p;\mathit{op};q$ is a shorthand for the
 constructor or extractor pattern $\mathit{op}(p, q)$.  The precedence and
 associativity of operators in patterns is the same as in
 [expressions](06-expressions.html#prefix,-infix,-and-postfix-operations).
@@ -280,7 +280,7 @@ shorthand for the constructor or extractor pattern $\mathit{op}(p, q_1
   Pattern   ::=  Pattern1 { `|' Pattern1 }
 ```
 
-A pattern alternative `$p_1$ | $\ldots$ | $p_n$`
+A _pattern alternative_ `$p_1$ | $\ldots$ | $p_n$`
 consists of a number of alternative patterns $p_i$. All alternative
 patterns are type checked with the expected type of the pattern. They
 may not bind variables other than wildcards. The alternative pattern
@@ -526,7 +526,7 @@ function's declared result type, `Number`.
   CaseClause      ::=  `case' Pattern [Guard] `=>' Block
 ```
 
-A pattern matching expression
+A _pattern matching expression_
 
 ```scala
 e match { case $p_1$ => $b_1$ $\ldots$ case $p_n$ => $b_n$ }
diff --git a/spec/09-top-level-definitions.md b/spec/09-top-level-definitions.md
index b8a8dc7e0a..1c2f7ec85e 100644
--- a/spec/09-top-level-definitions.md
+++ b/spec/09-top-level-definitions.md
@@ -23,7 +23,7 @@ A compilation unit consists of a sequence of packagings, import
 clauses, and class and object definitions, which may be preceded by a
 package clause.
 
-A compilation unit
+A _compilation unit_
 
 ```scala
 package $p_1$;
@@ -59,7 +59,7 @@ The exception to the implicit import of `scala.Predef` can be useful to hide, e.
 Packaging       ::=  ‘package’ QualId [nl] ‘{’ TopStatSeq ‘}’
 ```
 
-A package is a special object which defines a set of member classes,
+A _package_ is a special object which defines a set of member classes,
 objects and packages.  Unlike other objects, packages are not introduced
 by a definition.  Instead, the set of members of a package is determined by
 packagings.
@@ -100,7 +100,7 @@ are visible to each other without qualification.
 PackageObject   ::=  ‘package’ ‘object’ ObjectDef
 ```
 
-A package object `package object $p$ extends $t$` adds the
+A _package object_ `package object $p$ extends $t$` adds the
 members of template $t$ to the package $p$. There can be only one
 package object per package. The standard naming convention is to place
 the definition above in a file named `package.scala` that's