diff options
Diffstat (limited to 'spec/ruby/language/precedence_spec.rb')
| -rw-r--r-- | spec/ruby/language/precedence_spec.rb | 114 |
1 files changed, 56 insertions, 58 deletions
diff --git a/spec/ruby/language/precedence_spec.rb b/spec/ruby/language/precedence_spec.rb index 5a3c2861ce..edb990525e 100644 --- a/spec/ruby/language/precedence_spec.rb +++ b/spec/ruby/language/precedence_spec.rb @@ -14,46 +14,44 @@ require_relative 'fixtures/precedence' # the level below (as well as showing associativity within # the precedence level). -=begin -Excerpted from 'Programming Ruby: The Pragmatic Programmer's Guide' -Second Edition by Dave Thomas, Chad Fowler, and Andy Hunt, page 324 - -Table 22.4. Ruby operators (high to low precedence) -Method Operator Description ------------------------------------------------------------------------ - :: . - x* [ ] [ ]= Element reference, element set - x ** Exponentiation - x ! ~ + - Not, complement, unary plus and minus - (method names for the last two are +@ and -@) - x * / % Multiply, divide, and modulo - x + - Plus and minus - x >> << Right and left shift - x & “And” (bitwise for integers) - x ^ | Exclusive “or” and regular “or” (bitwise for integers) - x <= < > >= Comparison operators - x <=> == === != =~ !~ Equality and pattern match operators (!= - and !~ may not be defined as methods) - && Logical “and” - || Logical “or” - .. ... Range (inclusive and exclusive) - ? : Ternary if-then-else - = %= /= -= += |= &= Assignment - >>= <<= *= &&= ||= **= - defined? Check if symbol defined - not Logical negation - or and Logical composition - if unless while until Expression modifiers - begin/end Block expression ------------------------------------------------------------------------ - -* Operators marked with 'x' in the Method column are implemented as methods -and can be overridden (except != and !~ as noted). (But see the specs -below for implementations that define != and !~ as methods.) - -** These are not included in the excerpted table but are shown here for -completeness. -=end +# Excerpted from 'Programming Ruby: The Pragmatic Programmer's Guide' +# Second Edition by Dave Thomas, Chad Fowler, and Andy Hunt, page 324 +# +# Table 22.4. Ruby operators (high to low precedence) +# Method Operator Description +# ----------------------------------------------------------------------- +# :: . +# x* [ ] [ ]= Element reference, element set +# x ** Exponentiation +# x ! ~ + - Not, complement, unary plus and minus +# (method names for the last two are +@ and -@) +# x * / % Multiply, divide, and modulo +# x + - Plus and minus +# x >> << Right and left shift +# x & “And” (bitwise for integers) +# x ^ | Exclusive “or” and regular “or” (bitwise for integers) +# x <= < > >= Comparison operators +# x <=> == === != =~ !~ Equality and pattern match operators (!= +# and !~ may not be defined as methods) +# && Logical “and” +# || Logical “or” +# .. ... Range (inclusive and exclusive) +# ? : Ternary if-then-else +# = %= /= -= += |= &= Assignment +# >>= <<= *= &&= ||= **= +# defined? Check if symbol defined +# not Logical negation +# or and Logical composition +# if unless while until Expression modifiers +# begin/end Block expression +# ----------------------------------------------------------------------- +# +# * Operators marked with 'x' in the Method column are implemented as methods +# and can be overridden (except != and !~ as noted). (But see the specs +# below for implementations that define != and !~ as methods.) +# +# ** These are not included in the excerpted table but are shown here for +# completeness. # ----------------------------------------------------------------------- # It seems that this table is not correct anymore @@ -253,12 +251,12 @@ describe "Operators" do end it "<=> == === != =~ !~ are non-associative" do - -> { eval("1 <=> 2 <=> 3") }.should raise_error(SyntaxError) - -> { eval("1 == 2 == 3") }.should raise_error(SyntaxError) - -> { eval("1 === 2 === 3") }.should raise_error(SyntaxError) - -> { eval("1 != 2 != 3") }.should raise_error(SyntaxError) - -> { eval("1 =~ 2 =~ 3") }.should raise_error(SyntaxError) - -> { eval("1 !~ 2 !~ 3") }.should raise_error(SyntaxError) + -> { eval("1 <=> 2 <=> 3") }.should.raise(SyntaxError) + -> { eval("1 == 2 == 3") }.should.raise(SyntaxError) + -> { eval("1 === 2 === 3") }.should.raise(SyntaxError) + -> { eval("1 != 2 != 3") }.should.raise(SyntaxError) + -> { eval("1 =~ 2 =~ 3") }.should.raise(SyntaxError) + -> { eval("1 !~ 2 !~ 3") }.should.raise(SyntaxError) end it "<=> == === != =~ !~ have higher precedence than &&" do @@ -292,18 +290,18 @@ describe "Operators" do end it ".. ... are non-associative" do - -> { eval("1..2..3") }.should raise_error(SyntaxError) - -> { eval("1...2...3") }.should raise_error(SyntaxError) - end - - it ".. ... have higher precedence than ? :" do - # Use variables to avoid warnings - from = 1 - to = 2 - # These are flip-flop, not Range instances - (from..to ? 3 : 4).should == 3 - (from...to ? 3 : 4).should == 3 - end + -> { eval("1..2..3") }.should.raise(SyntaxError) + -> { eval("1...2...3") }.should.raise(SyntaxError) + end + + it ".. ... have higher precedence than ? :" do + # Use variables to avoid warnings + from = 1 + to = 2 + # These are flip-flop, not Range instances + (from..to ? 3 : 4).should == 3 + (from...to ? 3 : 4).should == 3 + end it "? : is right-associative" do (true ? 2 : 3 ? 4 : 5).should == 2 |