!1 Evaluator of expressions: $!--!{= =}
!2 Syntax
'''{{{       $!--!{= [format:] expression =} }}}'''
!3 Expression
An expression may be a combination of constants, variables, and opertors.  All internal calculations use the Java ''double'' numeric type.
!3 Format
A format is a specifier that describes the rendering of the numeric result.  The format specifier is described by the Java 5 String class's .format() method:
{{{       %[flags][width][.precision]conversion}}} *!note N.B., The ''[argument_index$]'' specifier is not permitted.
!3 Links
 * [[format string][http://java.sun.com/j2se/1.5.0/docs/api/java/util/Formatter.html#syntax]]
 * [[String.format()][http://java.sun.com/j2se/1.5.0/docs/api/java/lang/String.html#format(java.lang.String,%20java.lang.Object...)]]
 * [[String class][http://java.sun.com/j2se/1.5.0/docs/api/java/lang/String.html]]
!3 Examples
{{{    $!--!{= 12 + 23 =} renders (sand brackets) as [35]
    $!--!{=%5.4f:1.414=} : [1.4140]
    $!--!{=%05X:14+14=}  : [0001C]
    $!--!{= %-10s : 123 =}   : [123       ]}}}
!3 Operators supported
|Comment| !note Spaces between items are optional |
|'''Operator'''|'''Argument'''|'''Description'''|
|!c ''arg''   | ''constant or variable'' | Examples: 3, 12.4, 4E+8, $!--!{VALUE}, $!--!{some.var} |
|!c ''expr''  |!c ''expression''           | Any valid combination of arguments and optional operations and parentheses|
|!c '''+'''   |!c ''expr'' + ''expr''      | Addition |
|!c '''-'''   |!c -''expr''                | Unary negation |
|!c '''-'''   |!c ''expr'' - ''expr''      | Subtraction |
|!c '''!-*-!'''|!c ''expr'' !-*-! ''expr''  | Multiplication |
|!c '''/'''   |!c ''expr'' / ''expr''      | Division |
|!c '''^'''   |!c ''expr'' ^ ''expr''      | Exponentiation |
|!c '''sin''' |!c sin ''expr''             | Radian Sine of ''expr'' |
|!c '''cos''' |!c cos ''expr''             | Radian Cosine of ''expr'' |
|!c '''tan '''|!c cos ''expr''             | Radian Tangent of ''expr'' |
|!c '''( )'''  |!c ( ''expr'' )             | Parenthetical grouping of an expression |
#-----------------------------------------------------------------
-----
!3 Test Blank Expressions
''' Build blank expression page '''
!|script|
| start | Page Builder|
| line |~1a:${==}~|
| line |~1b:${= =}~|
| line |~1c:${=  =}~|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern |matches?|
| contents | ~1a:~   |true    |
| contents | ~1b:~   |true    |
| contents | ~1c:~   |true    |

#-----------------------------------------------------------------
-----
!3 Test Single Argument Expressions
''' Build expression page '''
!|script|
| start | Page Builder|
| line |!- ~2a:${=3=}~   -!|
| line |!- ~2b:${= 4.2 =}~  -!|
| line |!- ~2c:${= 2E+1 =}~ -!|
| line |!- ~2d:${=  2.3E+42  =}~ -!|
| line |!- ~2e:${=  4.2E + 24  =}~ -!|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern     |matches?|
| contents | ~2a:3~      |true    |
| contents | ~2b:4.2~    |true    |
| contents | ~2c:20~     |true    |
| contents | ~2d:2.3E+42~|true    |
| contents | ~2e:4.2E+24~|true    |

#-----------------------------------------------------------------
-----
!3 Test spaces around experssions
''' Build expression page '''
!|script|
| start | Page Builder|
| line |!- ~3a:${=1+1=}~ -!|
| line |!- ~3b:${=2 + 2=}~ -!|
| line |!- ~3c:${= 3 + 3=}~ -!|
| line |!- ~3d:${=4 + 4 =}~ -!|
| line |!- ~3e:${=5 +5 =}~ -!|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern |matches?|
| contents | ~3a:2~  |true    |
| contents | ~3b:4~  |true    |
| contents | ~3c:6~  |true    |
| contents | ~3d:8~  |true    |
| contents | ~3e:10~ |true    |

#-----------------------------------------------------------------
-----
!3 Test each operator
''' Build expression page '''
!|script|
| start | Page Builder|
| line |!- ~4plus:${= 1 + 2 =}~     -!|
| line |!- ~4minus:${= 2 - 3 =}~    -!|
| line |!- ~4unary:${= -12 =}~      -!|
| line |!- ~4mult:${= 3 * 4 =}~     -!|
| line |!- ~4div:${= 4 / 5 =}~      -!|
| line |!- ~4exp:${=%2d: 5 ^ 6 =}~  -!|
| line |!- ~4sin1:${=%5.4f: sin0.39269875   =}~ -!|
| line |!- ~4sin2:${=%5.4f: sin 0.39269875  =}~ -!|
| line |!- ~4sin3:${=%5.4f: sin(0.39269875) =}~ -!|
| line |!- ~4sin4:${=%5.4f: sin(3.14159/8)  =}~ -!|
| line |!- ~4sin5:${=%5.4f: sin (3.14159/8) =}~ -!|
| line |!- ~4cos:${=%5.4f: cos(3.14159 / 8) =}~ -!|
| line |!- ~4tan:${=%5.4f: tan(3.14159 / 8) =}~ -!|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern        |matches?|
| contents | ~4plus:3~      |true    |
| contents | ~4minus:-1~    |true    |
| contents | ~4unary:-12~   |true    |
| contents | ~4mult:12~     |true    |
| contents | ~4div:0.8~     |true    |
| contents | ~4exp:15625~   |true    |
| contents | ~4sin1:0.3827~ |true    |
| contents | ~4sin2:0.3827~ |true    |
| contents | ~4sin3:0.3827~ |true    |
| contents | ~4sin4:0.3827~ |true    |
| contents | ~4sin5:0.3827~ |true    |
| contents | ~4cos:0.9239~  |true    |
| contents | ~4tan:0.4142~  |true    |

#-----------------------------------------------------------------
-----
!3 Test parentheses
''' Build expression page '''
!|script|
| start | Page Builder|
| line |!- ~5a:${= 2 * 3 + 4 / 2 - 3             =}~ -!|
| line |!- ~5b:${= 2 * ( 3 + 4 ) / 2 - 3         =}~ -!|
| line |!- ~5c:${= 2 * ( 3 + 4 ) / ( 2 - 3 )     =}~ -!|
| line |!- ~5d:${= 2 * ( 3 + ( 4 / ( 2 - 3 ) ) ) =}~ -!|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern  |matches?|
| contents | ~5a:5~   |true    |
| contents | ~5b:4~   |true    |
| contents | ~5c:-14~ |true    |
| contents | ~5d:-2~  |true    |

#-----------------------------------------------------------------
-----
!3 Test formatting
''' Build expression page '''
!|script|
| start | Page Builder|
| line |!- ~6a:${=%d:2                =}~ -!|
| line |!- ~6b:${= %d : 3.2           =}~ -!|
| line |!- ~6c:${=%02d: 2 + 1        =}~  -!|
| line |!- ~6d:${= %4.4f: 2.2 / 3.4 =}~   -!|
| line |!- ~6e:${=%03o: 16 =}~            -!|
| line |!- ~6f:${= %03o : 18 =}~          -!|
| line |!- ~6g:${=%03x: 26 =}~            -!|
| line |!- ~6h:${=%03X: 27 =}~            -!|
| line |!- ~6i:${= %-12s : 123 =}~        -!|
| line |!- ~6j:${=%TY: 73422123127 =}~    -!|
| line |!- ~6k:${=%b: 27 =}~              -!|
| line |!- ~6l:${=%b: 0 =}~               -!|
| line |!- ~6m:${=%B: 27 =}~              -!|
| line |!- ~6n:${=%B: 0 =}~               -!|
| line |!- ~6o:${= % d : 3.2          =}~ -!|
| page | ExpressionPage  |

''' Render it '''
!|Response Requester|
| uri            | valid? |
| ExpressionPage | true   |

!**> Contents
!|Response Examiner|
|type    | string? |
|contents|         |

!|Response Examiner|
|type    | wrapped html? |
|contents|               |

***!

''' Verify results '''
!|Response Examiner|
| type     | pattern     |matches?|
| contents | ~6a:2~      |true    |
| contents | ~6b:3~      |true    |
| contents | ~6c:03~     |true    |
| contents | ~6d:0.6471~ |true    |
| contents | ~6e:020~    |true    |
| contents | ~6f:022~    |true    |
| contents | ~6g:01a~    |true    |
| contents | ~6h:01B~    |true    |
| contents | ~6i:123         ~|true|
| contents | ~6j:1972~   |true    |
| contents | ~6k:true~   |true    |
| contents | ~6l:false~  |true    |
| contents | ~6m:true~   |true    |
| contents | ~6n:false~  |true    |
| contents | ~6o: 3~      |true    |

#---[EOT]---