Doc: more details on the syntax of the numbers, strings and boolean
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doc/Expr.adoc
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doc/Expr.adoc
@ -22,7 +22,7 @@ Expressions calculator
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toc::[]
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#TODO: Work in progress (last update on 2024/05/15, 10:00 p.m.)#
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#TODO: Work in progress (last update on 2024/05/16, 7:08 a.m.)#
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== Expr
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_Expr_ is a GO package capable of analysing, interpreting and calculating expressions.
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@ -33,9 +33,9 @@ _Expr_ is a GO package capable of analysing, interpreting and calculating expres
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image::expression-diagram.png[]
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=== `dev-expr` test tool
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`dev-expr` is a simple program that can be used to evaluate expressions interactively. As its name suggests, it was created for testing purpose. In fact, beyond in additon to the automatic test suite based on the Go test framework, `dev-expr` provides an important aid for quickly testing of new features during their development.
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`dev-expr` is a simple program that can be used to evaluate expressions interactively. As its name suggests, it was created for testing purpose. In fact, in additon to the automatic verification test suite based on the Go test framework, `dev-expr` provides an important aid for quickly testing of new features during their development.
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It cat work as a _REPL_, _**R**ead-**E**xecute-**P**rint-**L**oop_, or it can process expression acquired from files or standard input.
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`dev-expr` can work as a _REPL_, _**R**ead-**E**xecute-**P**rint-**L**oop_, or it can process expression acquired from files or standard input.
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The program can be downloaded from https://git.portale-stac.it/go-pkg/-/packages/generic/dev-expr/[dev-expr].
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@ -46,19 +46,21 @@ Here are some examples of execution.
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----
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# Assume the expr source directory. Type 'exit' or Ctrl+D to quit the program.
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[user]$ tools/expr -- Expressions calculator v1.7.0,2024/05/08 (celestino.amoroso@portale-stac.it)
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Type help to get the list of command.
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[user]$ ./dev-expr
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expr -- Expressions calculator v1.7.1(build 2),2024/05/16 (celestino.amoroso@portale-stac.it)
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Based on the Expr package v0.10.0
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Type help to get the list of available commands
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See also https://git.portale-stac.it/go-pkg/expr/src/branch/main/README.adoc
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>>> help
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--- REPL commands:
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source -- Load a file as input
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tty -- Enable/Disable ansi output <1>
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base -- Set the integer output base: 2, 8, 10, or 16
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exit -- Exit the program
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help -- Show command list
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ml -- Enable/Disable multi-line output
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mods -- List builtin modules
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source -- Load a file as input
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tty -- Enable/Disable ansi output <1>
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--- Command line options:
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-b <builtin> Import builtin modules.
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@ -80,9 +82,12 @@ Here are some examples of execution.
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.REPL examples
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[source,shell]
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----
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[user]$ tools/expr -- Expressions calculator v1.6.1,2024/05/06 (celestino.amoroso@portale-stac.it)
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Type help to get the list of command.
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[user]$ ./dev-expr
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expr -- Expressions calculator v1.7.1(build 2),2024/05/16 (celestino.amoroso@portale-stac.it)
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Based on the Expr package v0.10.0
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Type help to get the list of available commands
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See also https://git.portale-stac.it/go-pkg/expr/src/branch/main/README.adoc
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>>> 2+3
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5
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>>> 2+3*(4-1.5)
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@ -166,6 +171,20 @@ _sign_ = "**+**" | "**-**" +
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_dec-seq_ = _see-integer-literal-syntax_
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====
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.Examples
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`>>>` [blue]`1.0` +
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[green]`1` +
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`>>>` [blue]`0.123` +
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[green]`0.123` +
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`>>>` [blue]`4.5e+3` +
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[green]`4500` +
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`>>>` [blue]`4.5E-33` +
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[green]`4.5e-33` +
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`>>>` [blue]`4.5E-3` +
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[green]`0.0045` +
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`>>>` [blue]`4.5E10` +
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[green]`4.5e+10` +
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.Arithmetic operators
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[cols="^1,^2,6,4"]
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@ -196,19 +215,19 @@ _digit-seq_ = _see-integer-literal-syntax_ +
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// ----
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`>>>` [blue]`1 | 2` +
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[green]`1|2` +
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`>>>` [blue]`4|6` +
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[green]`2|3` [gray]_Fractions are always reduced to their lowest terms_ +
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`>>>` [blue]`4|6` [gray]_// Fractions are always reduced to their lowest terms_ +
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[green]`2|3` +
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`>>>` [blue]`1|2 + 2|3` +
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[green]`7|6` +
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`>>>` [blue]`1|2 * 2|3` +
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[green]`1|3` +
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`>>>` [blue]`1|2 / 1|3` +
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[green]`3|2` +
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`>>>` [blue]`1|2 ./ 1|3` [gray]_Force decimal division_ +
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`>>>` [blue]`1|2 ./ 1|3` [gray]_// Force decimal division_ +
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[green]`1.5` +
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`>>>` [blue]`-1|2` +
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[green]`-1|2` +
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`>>>` [blue]`1|-2` [gray]_Wrong sign specification_ +
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`>>>` [blue]`1|-2` [gray]_// Invalid sign specification_ +
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[red]_Eval Error: [1:3] infix operator "|" requires two non-nil operands, got 1_ +
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`>>>` [blue]`1|(-2)` +
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[green]`-1|2`
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@ -226,7 +245,18 @@ Fractions can be used together with integers and floats in expressions.
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=== Strings
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Strings are character sequences enclosed between two double quote [blue]`"`. Example: [blue]`"I'm a string"`.
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Strings are character sequences enclosed between two double quote [blue]`"`.
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.Examples
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`>>>` [blue]`"I'm a string"` +
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[green]`I'm a string` +
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`>>>` [blue]`"123abc?!"` +
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[green]`123abc?!` +
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`>>>` [blue]`"123\nabc"` +
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[green]`123` +
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[green]`abc` +
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`>>>` [blue]`"123\tabc"` +
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[green]`123{nbsp}{nbsp}{nbsp}{nbsp}abc`
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Some arithmetic operators can also be used with strings.
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@ -244,10 +274,9 @@ Some arithmetic operators can also be used with strings.
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The items of strings can be accessed using the dot `.` operator.
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.Item access syntax
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[source,bnf]
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----
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<item> ::= <string-expr>"."<index-expr>
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----
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====
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_item_ = _string-expr_ "**.**" _integer-expr_
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====
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.String examples
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`>>>` [blue]`s="abc"` [gray]_assign the string to variable s_ +
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@ -262,26 +291,25 @@ The items of strings can be accessed using the dot `.` operator.
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[green]`3` +
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=== Boolean
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Boolean data type has two values only: _true_ and _false_. Relational and Boolean expressions produce Boolean values.
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Boolean data type has two values only: [blue]_true_ and [blue]_false_. Relational and boolean expressions result in boolean values.
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.Relational operators
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[cols="^1,^2,6,4"]
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|===
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| Symbol | Operation | Description | Examples
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| [blue]`==` | _Equal_ | True if the left value is equal to the right one | [blue]`5 == 2` _[false]_ +
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[blue]`"a" == "a"` _[true]_
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| [blue]`!=` | _Not Equal_ | True if the left value is NOT equal to the right one | [blue]`5 != 2` _[true]_ +
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[blue]`"a" != "a"` _[false]_
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| [blue]`<` | _Less_ | True if the left value is less than the right one | [blue]`5 < 2` _[false]_ +
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[blue]`"a" < "b"` _[true]_
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| [blue]`\<=` | _Less or Equal_ | True if the left value is less than or equal to the right one | [blue]`5 \<= 2` _[false]_ +
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[blue]`"b" \<= "b"` _[true]_
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| [blue]`>` | _Greater_ | True if the left value is greater than the right one | [blue]`5 > 2` _[true]_ +
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[blue]`"a" < "b"` _[false]_
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| [blue]`>=` | _Greater or Equal_ | True if the left value is greater than or equal to the right one | [blue]`5 >= 2` _[true]_ +
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[blue]`"b" \<= "b"` _[true]_
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| [blue]`==` | _Equal_ | True if the left value is equal to the right one | [blue]`5 == 2` -> _false_ +
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[blue]`"a" == "a"` -> _true_
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| [blue]`!=` | _Not Equal_ | True if the left value is NOT equal to the right one | [blue]`5 != 2` -> _true_ +
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[blue]`"a" != "a"` -> _false_
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| [blue]`<` | _Less_ | True if the left value is less than the right one | [blue]`5 < 2` -> _false_ +
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[blue]`"a" < "b"` -> _true_
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| [blue]`\<=` | _Less or Equal_ | True if the left value is less than or equal to the right one | [blue]`5 \<= 2` -> _false_ +
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[blue]`"b" \<= "b"` -> _true_
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| [blue]`>` | _Greater_ | True if the left value is greater than the right one | [blue]`5 > 2` -> _true_ +
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[blue]`"a" < "b"` -> _false_
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| [blue]`>=` | _Greater or Equal_ | True if the left value is greater than or equal to the right one | [blue]`5 >= 2` -> _true_ +
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[blue]`"b" \<= "b"` -> _true_
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|===
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@ -290,19 +318,19 @@ Boolean data type has two values only: _true_ and _false_. Relational and Boolea
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|===
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| Symbol | Operation | Description | Examples
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| [blue]`NOT` | _Not_ | True if the right value is false | [blue]`NOT true` _[false]_ +
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[blue]`NOT (2 < 1)` _[true]_
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| [blue]`NOT` | _Not_ | True if the right value is false | [blue]`NOT true` -> _false_ +
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[blue]`NOT (2 < 1)` -> _true_
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| [blue]`AND` / [blue]`&&` | _And_ | True if both left and right values are true | [blue]`false && true` _[false]_ +
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[blue]`"a" < "b" AND NOT (2 < 1)` _[true]_
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| [blue]`AND` / [blue]`&&` | _And_ | True if both left and right values are true | [blue]`false && true` -> _false_ +
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[blue]`"a" < "b" AND NOT (2 < 1)` -> _true_
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| [blue]`OR` / [blue]`\|\|` | _Or_ | True if at least one of the left and right values integers true| [blue]`false or true` _[true]_ +
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[blue]`"a" == "b" OR (2 == 1)` _[false]_
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| [blue]`OR` / [blue]`\|\|` | _Or_ | True if at least one of the left and right values integers true| [blue]`false or true` -> _true_ +
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[blue]`"a" == "b" OR (2 == 1)` -> _false_
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|===
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[CAUTION]
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====
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Currently, boolean operations are evaluated using _short cut evaluation_. This means that, if the left expression of operators [blue]`and` and [blue]`or` is sufficient to establish the result of the whole operation, the right expression would not evaluated at all.
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Currently, boolean operations are evaluated using _short cut evaluation_. This means that, if the left expression of the [blue]`and` and [blue]`or` operators is sufficient to establish the result of the whole operation, the right expression would not evaluated at all.
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.Example
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[source,go]
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110
doc/Expr.html
110
doc/Expr.html
@ -584,7 +584,7 @@ pre.rouge .ss {
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<div class="sectionbody">
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<!-- toc disabled -->
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<div class="paragraph">
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<p><mark>TODO: Work in progress (last update on 2024/05/15, 10:00 p.m.)</mark></p>
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<p><mark>TODO: Work in progress (last update on 2024/05/16, 7:08 a.m.)</mark></p>
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</div>
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</div>
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</div>
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@ -608,10 +608,10 @@ pre.rouge .ss {
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<div class="sect2">
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<h3 id="_dev_expr_test_tool"><a class="anchor" href="#_dev_expr_test_tool"></a><a class="link" href="#_dev_expr_test_tool">1.2. <code>dev-expr</code> test tool</a></h3>
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<div class="paragraph">
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<p><code>dev-expr</code> is a simple program that can be used to evaluate expressions interactively. As its name suggests, it was created for testing purpose. In fact, beyond in additon to the automatic test suite based on the Go test framework, <code>dev-expr</code> provides an important aid for quickly testing of new features during their development.</p>
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<p><code>dev-expr</code> is a simple program that can be used to evaluate expressions interactively. As its name suggests, it was created for testing purpose. In fact, in additon to the automatic verification test suite based on the Go test framework, <code>dev-expr</code> provides an important aid for quickly testing of new features during their development.</p>
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</div>
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<div class="paragraph">
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<p>It cat work as a <em>REPL</em>, <em><strong>R</strong>ead-<strong>E</strong>xecute-<strong>P</strong>rint-<strong>L</strong>oop</em>, or it can process expression acquired from files or standard input.</p>
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<p><code>dev-expr</code> can work as a <em>REPL</em>, <em><strong>R</strong>ead-<strong>E</strong>xecute-<strong>P</strong>rint-<strong>L</strong>oop</em>, or it can process expression acquired from files or standard input.</p>
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</div>
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<div class="paragraph">
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<p>The program can be downloaded from <a href="https://git.portale-stac.it/go-pkg/-/packages/generic/dev-expr/">dev-expr</a>.</p>
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@ -624,19 +624,21 @@ pre.rouge .ss {
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<div class="content">
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<pre class="rouge highlight"><code data-lang="shell"><span class="c"># Assume the expr source directory. Type 'exit' or Ctrl+D to quit the program.</span>
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<span class="o">[</span>user]<span class="nv">$ </span>tools/expr <span class="nt">--</span> Expressions calculator v1.7.0,2024/05/08 <span class="o">(</span>celestino.amoroso@portale-stac.it<span class="o">)</span>
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Type <span class="nb">help </span>to get the list of command.
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<span class="o">[</span>user]<span class="nv">$ </span>./dev-expr
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<span class="nb">expr</span> <span class="nt">--</span> Expressions calculator v1.7.1<span class="o">(</span>build 2<span class="o">)</span>,2024/05/16 <span class="o">(</span>celestino.amoroso@portale-stac.it<span class="o">)</span>
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Based on the Expr package v0.10.0
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Type <span class="nb">help </span>to get the list of available commands
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See also https://git.portale-stac.it/go-pkg/expr/src/branch/main/README.adoc
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<span class="o">>>></span> <span class="nb">help</span>
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<span class="nt">---</span> REPL commands:
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<span class="nb">source</span> <span class="nt">--</span> Load a file as input
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<span class="nb">tty</span> <span class="nt">--</span> Enable/Disable ansi output <i class="conum" data-value="1"></i><b>(1)</b>
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base <span class="nt">--</span> Set the integer output base: 2, 8, 10, or 16
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<span class="nb">exit</span> <span class="nt">--</span> Exit the program
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<span class="nb">help</span> <span class="nt">--</span> Show <span class="nb">command </span>list
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ml <span class="nt">--</span> Enable/Disable multi-line output
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mods <span class="nt">--</span> List <span class="nb">builtin </span>modules
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<span class="nb">source</span> <span class="nt">--</span> Load a file as input
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<span class="nb">tty</span> <span class="nt">--</span> Enable/Disable ansi output <i class="conum" data-value="1"></i><b>(1)</b>
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<span class="nt">---</span> Command line options:
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<span class="nt">-b</span> <<span class="nb">builtin</span><span class="o">></span> Import <span class="nb">builtin </span>modules.
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@ -667,9 +669,12 @@ pre.rouge .ss {
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<div class="listingblock">
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<div class="title">REPL examples</div>
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<div class="content">
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<pre class="rouge highlight"><code data-lang="shell"><span class="o">[</span>user]<span class="nv">$ </span>tools/expr <span class="nt">--</span> Expressions calculator v1.6.1,2024/05/06 <span class="o">(</span>celestino.amoroso@portale-stac.it<span class="o">)</span>
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Type <span class="nb">help </span>to get the list of command.
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<pre class="rouge highlight"><code data-lang="shell"><span class="o">[</span>user]<span class="nv">$ </span>./dev-expr
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<span class="nb">expr</span> <span class="nt">--</span> Expressions calculator v1.7.1<span class="o">(</span>build 2<span class="o">)</span>,2024/05/16 <span class="o">(</span>celestino.amoroso@portale-stac.it<span class="o">)</span>
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Based on the Expr package v0.10.0
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Type <span class="nb">help </span>to get the list of available commands
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See also https://git.portale-stac.it/go-pkg/expr/src/branch/main/README.adoc
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<span class="o">>>></span> 2+3
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5
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<span class="o">>>></span> 2+3<span class="k">*</span><span class="o">(</span>4-1.5<span class="o">)</span>
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@ -836,6 +841,21 @@ pre.rouge .ss {
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</div>
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</div>
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</div>
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<div class="paragraph">
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<div class="title">Examples</div>
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<p><code>>>></code> <code class="blue">1.0</code><br>
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<code class="green">1</code><br>
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<code>>>></code> <code class="blue">0.123</code><br>
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<code class="green">0.123</code><br>
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<code>>>></code> <code class="blue">4.5e+3</code><br>
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<code class="green">4500</code><br>
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<code>>>></code> <code class="blue">4.5E-33</code><br>
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<code class="green">4.5e-33</code><br>
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<code>>>></code> <code class="blue">4.5E-3</code><br>
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<code class="green">0.0045</code><br>
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<code>>>></code> <code class="blue">4.5E10</code><br>
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<code class="green">4.5e+10</code><br></p>
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</div>
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<table class="tableblock frame-all grid-all stretch">
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<caption class="title">Table 2. Arithmetic operators</caption>
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<colgroup>
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@ -906,19 +926,19 @@ pre.rouge .ss {
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<div class="title">Examples</div>
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<p><code>>>></code> <code class="blue">1 | 2</code><br>
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<code class="green">1|2</code><br>
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<code>>>></code> <code class="blue">4|6</code><br>
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<code class="green">2|3</code> <em class="gray">Fractions are always reduced to their lowest terms</em><br>
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<code>>>></code> <code class="blue">4|6</code> <em class="gray">// Fractions are always reduced to their lowest terms</em><br>
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<code class="green">2|3</code><br>
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<code>>>></code> <code class="blue">1|2 + 2|3</code><br>
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<code class="green">7|6</code><br>
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<code>>>></code> <code class="blue">1|2 * 2|3</code><br>
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<code class="green">1|3</code><br>
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<code>>>></code> <code class="blue">1|2 / 1|3</code><br>
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<code class="green">3|2</code><br>
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<code>>>></code> <code class="blue">1|2 ./ 1|3</code> <em class="gray">Force decimal division</em><br>
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<code>>>></code> <code class="blue">1|2 ./ 1|3</code> <em class="gray">// Force decimal division</em><br>
|
||||
<code class="green">1.5</code><br>
|
||||
<code>>>></code> <code class="blue">-1|2</code><br>
|
||||
<code class="green">-1|2</code><br>
|
||||
<code>>>></code> <code class="blue">1|-2</code> <em class="gray">Wrong sign specification</em><br>
|
||||
<code>>>></code> <code class="blue">1|-2</code> <em class="gray">// Invalid sign specification</em><br>
|
||||
<em class="red">Eval Error: [1:3] infix operator "|" requires two non-nil operands, got 1</em><br>
|
||||
<code>>>></code> <code class="blue">1|(-2)</code><br>
|
||||
<code class="green">-1|2</code></p>
|
||||
@ -939,7 +959,19 @@ pre.rouge .ss {
|
||||
<div class="sect2">
|
||||
<h3 id="_strings"><a class="anchor" href="#_strings"></a><a class="link" href="#_strings">2.2. Strings</a></h3>
|
||||
<div class="paragraph">
|
||||
<p>Strings are character sequences enclosed between two double quote <code class="blue">"</code>. Example: <code class="blue">"I’m a string"</code>.</p>
|
||||
<p>Strings are character sequences enclosed between two double quote <code class="blue">"</code>.</p>
|
||||
</div>
|
||||
<div class="paragraph">
|
||||
<div class="title">Examples</div>
|
||||
<p><code>>>></code> <code class="blue">"I’m a string"</code><br>
|
||||
<code class="green">I’m a string</code><br>
|
||||
<code>>>></code> <code class="blue">"123abc?!"</code><br>
|
||||
<code class="green">123abc?!</code><br>
|
||||
<code>>>></code> <code class="blue">"123\nabc"</code><br>
|
||||
<code class="green">123</code><br>
|
||||
<code class="green">abc</code><br>
|
||||
<code>>>></code> <code class="blue">"123\tabc"</code><br>
|
||||
<code class="green">123    abc</code></p>
|
||||
</div>
|
||||
<div class="paragraph">
|
||||
<p>Some arithmetic operators can also be used with strings.</p>
|
||||
@ -979,10 +1011,12 @@ pre.rouge .ss {
|
||||
<div class="paragraph">
|
||||
<p>The items of strings can be accessed using the dot <code>.</code> operator.</p>
|
||||
</div>
|
||||
<div class="listingblock">
|
||||
<div class="title">Item access syntax</div>
|
||||
<div class="exampleblock">
|
||||
<div class="title">Example 4. Item access syntax</div>
|
||||
<div class="content">
|
||||
<pre class="rouge highlight"><code data-lang="bnf"><item> ::= <string-expr>"."<index-expr></code></pre>
|
||||
<div class="paragraph">
|
||||
<p><em>item</em> = <em>string-expr</em> "<strong>.</strong>" <em>integer-expr</em></p>
|
||||
</div>
|
||||
</div>
|
||||
</div>
|
||||
<div class="paragraph">
|
||||
@ -1002,7 +1036,7 @@ pre.rouge .ss {
|
||||
<div class="sect2">
|
||||
<h3 id="_boolean"><a class="anchor" href="#_boolean"></a><a class="link" href="#_boolean">2.3. Boolean</a></h3>
|
||||
<div class="paragraph">
|
||||
<p>Boolean data type has two values only: <em>true</em> and <em>false</em>. Relational and Boolean expressions produce Boolean values.</p>
|
||||
<p>Boolean data type has two values only: <em class="blue">true</em> and <em class="blue">false</em>. Relational and boolean expressions result in boolean values.</p>
|
||||
</div>
|
||||
<table class="tableblock frame-all grid-all stretch">
|
||||
<caption class="title">Table 4. Relational operators</caption>
|
||||
@ -1025,43 +1059,43 @@ pre.rouge .ss {
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">==</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Equal</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is equal to the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 == 2</code> <em>[false]</em><br>
|
||||
<code class="blue">"a" == "a"</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 == 2</code> → <em>false</em><br>
|
||||
<code class="blue">"a" == "a"</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">!=</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Not Equal</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is NOT equal to the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 != 2</code> <em>[true]</em><br>
|
||||
<code class="blue">"a" != "a"</code> <em>[false]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 != 2</code> → <em>true</em><br>
|
||||
<code class="blue">"a" != "a"</code> → <em>false</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue"><</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Less</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is less than the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 < 2</code> <em>[false]</em><br>
|
||||
<code class="blue">"a" < "b"</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 < 2</code> → <em>false</em><br>
|
||||
<code class="blue">"a" < "b"</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue"><=</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Less or Equal</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is less than or equal to the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 <= 2</code> <em>[false]</em><br>
|
||||
<code class="blue">"b" <= "b"</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 <= 2</code> → <em>false</em><br>
|
||||
<code class="blue">"b" <= "b"</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">></code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Greater</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is greater than the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 > 2</code> <em>[true]</em><br>
|
||||
<code class="blue">"a" < "b"</code> <em>[false]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 > 2</code> → <em>true</em><br>
|
||||
<code class="blue">"a" < "b"</code> → <em>false</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">>=</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Greater or Equal</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the left value is greater than or equal to the right one</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 >= 2</code> <em>[true]</em><br>
|
||||
<code class="blue">"b" <= "b"</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">5 >= 2</code> → <em>true</em><br>
|
||||
<code class="blue">"b" <= "b"</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
@ -1086,22 +1120,22 @@ pre.rouge .ss {
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">NOT</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Not</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if the right value is false</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">NOT true</code> <em>[false]</em><br>
|
||||
<code class="blue">NOT (2 < 1)</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">NOT true</code> → <em>false</em><br>
|
||||
<code class="blue">NOT (2 < 1)</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">AND</code> / <code class="blue">&&</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>And</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if both left and right values are true</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">false && true</code> <em>[false]</em><br>
|
||||
<code class="blue">"a" < "b" AND NOT (2 < 1)</code> <em>[true]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">false && true</code> → <em>false</em><br>
|
||||
<code class="blue">"a" < "b" AND NOT (2 < 1)</code> → <em>true</em></p></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">OR</code> / <code class="blue">||</code></p></td>
|
||||
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Or</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock">True if at least one of the left and right values integers true</p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">false or true</code> <em>[true]</em><br>
|
||||
<code class="blue">"a" == "b" OR (2 == 1)</code> <em>[false]</em></p></td>
|
||||
<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">false or true</code> → <em>true</em><br>
|
||||
<code class="blue">"a" == "b" OR (2 == 1)</code> → <em>false</em></p></td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table>
|
||||
@ -1113,7 +1147,7 @@ pre.rouge .ss {
|
||||
</td>
|
||||
<td class="content">
|
||||
<div class="paragraph">
|
||||
<p>Currently, boolean operations are evaluated using <em>short cut evaluation</em>. This means that, if the left expression of operators <code class="blue">and</code> and <code class="blue">or</code> is sufficient to establish the result of the whole operation, the right expression would not evaluated at all.</p>
|
||||
<p>Currently, boolean operations are evaluated using <em>short cut evaluation</em>. This means that, if the left expression of the <code class="blue">and</code> and <code class="blue">or</code> operators is sufficient to establish the result of the whole operation, the right expression would not evaluated at all.</p>
|
||||
</div>
|
||||
<div class="listingblock">
|
||||
<div class="title">Example</div>
|
||||
@ -1627,7 +1661,7 @@ The value on the left side of <code class="blue">=</code> must be an identifier.
|
||||
</div>
|
||||
<div id="footer">
|
||||
<div id="footer-text">
|
||||
Last updated 2024-05-15 22:00:00 +0200
|
||||
Last updated 2024-05-16 07:10:03 +0200
|
||||
</div>
|
||||
</div>
|
||||
</body>
|
||||
|
||||
Loading…
Reference in New Issue
Block a user