Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
syntax: implement support for ES6 template literals
Implement support for ECMAScript 6 template literals which allow simple interpolation of variable values into strings without resorting to `sprintf()` or manual string concatenation. Signed-off-by: Jo-Philipp Wich <jo@mein.io>
- Loading branch information
Showing
5 changed files
with
209 additions
and
10 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,102 @@ | ||
| The ucode language supports ES6 template literals for easy interpolation | ||
| of expression results into strings. | ||
|
|
||
|
|
||
| 1. Simple template literals are equivalent to strings. | ||
|
|
||
| -- Testcase -- | ||
| {{ `foo` === 'foo' }} | ||
| -- End -- | ||
|
|
||
| -- Expect stdout -- | ||
| true | ||
| -- End -- | ||
|
|
||
|
|
||
| 2. Template literals may embed expressions using `${...}` placeholder notation. | ||
|
|
||
| -- Testcase -- | ||
| {% | ||
| let x = 2; | ||
| let y = 4; | ||
|
|
||
| print(`The result of ${x} * ${y} is ${x * y}\n`); | ||
| %} | ||
| -- End -- | ||
|
|
||
| -- Expect stdout -- | ||
| The result of 2 * 4 is 8 | ||
| -- End -- | ||
|
|
||
|
|
||
| 3. Template literals may be nested. | ||
|
|
||
| -- Testcase -- | ||
| {% | ||
| let isFoo = false; | ||
| let isBar = true; | ||
|
|
||
| print(`Foo is ${isFoo} and ${isBar ? `bar is ${isBar}` : `nothing else`}!\n`); | ||
| %} | ||
| -- End -- | ||
|
|
||
| -- Expect stdout -- | ||
| Foo is false and bar is true! | ||
| -- End -- | ||
|
|
||
|
|
||
| 4. Placeholder expression results are implicitly stringified. | ||
|
|
||
| -- Testcase -- | ||
| {% | ||
| let o1 = { foo: true }; | ||
| let o2 = proto({ color: "red" }, { tostring: function() { return `I am a ${this.color} object` } }); | ||
|
|
||
| print(`The first object is ${o1} and the second says "${o2}".\n`); | ||
| %} | ||
| -- End -- | ||
|
|
||
| -- Expect stdout -- | ||
| The first object is { "foo": true } and the second says "I am a red object". | ||
| -- End -- | ||
|
|
||
|
|
||
| 5. Escaping either `$` or `{` prevents interpolation as placeholder, sole `$` | ||
| characters bear no special meaning. | ||
|
|
||
| -- Testcase -- | ||
| {% | ||
| printf("%.J\n", [ | ||
| `foo \${bar} baz`, | ||
| `foo $\{bar} baz`, | ||
| `foo $bar baz` | ||
| ]); | ||
| %} | ||
| -- End -- | ||
|
|
||
| -- Expect stdout -- | ||
| [ | ||
| "foo ${bar} baz", | ||
| "foo ${bar} baz", | ||
| "foo $bar baz" | ||
| ] | ||
| -- End -- | ||
|
|
||
|
|
||
| 6. Unterminated placeholder expressions are a synatax error. | ||
|
|
||
| -- Testcase -- | ||
| {{ | ||
| `foo ${ bar` | ||
| }} | ||
| -- End -- | ||
|
|
||
| -- Expect stderr -- | ||
| Syntax error: Unterminated string | ||
| In line 2, byte 13: | ||
|
|
||
| ` `foo ${ bar`` | ||
| Near here -----^ | ||
|
|
||
|
|
||
| -- End -- |