assert_true and assert_false interfaces

This page explains the assert_true and assert_false function interfaces.

What interfaces are these?

The assert_true function interface asserts a specified Boolean value is true. Conversely, the assert_false function interface asserts a specified Boolean value is false.

See also

Basic usage

The assert_true and assert_false interfaces require value argument. The type_strict and msg arguments are optional (default value of the type_strict argument is True).

If the type_strict argument is True, the assertion will use the JavaScript strict comparison operator (===). For instance, if the value is Int(1) and the type_strict is True, an assertion will fail (because of the comparison between the Boolean and Int). Conversely, if the type_strict is False, Int(1) will pass the assert_true assertion.

These interfaces display an assertion result on the browser console.

The following assertion example (assert_true and value is the Boolean(True)) passes:

import apysc as ap

stage: ap.Stage = ap.Stage(
    stage_width=0,
    stage_height=0,
    background_color=ap.Color("#333"),
    stage_elem_id="stage",
)

bool_1: ap.Boolean = ap.Boolean(True)
ap.assert_true(bool_1, msg="Boolean value is not True!")

ap.save_overall_html(dest_dir_path="assert_true_basic_usage_1/")

[assert_true]
Right-side variable name: b_3
Left value: true right value: true

The following assertion example (assert_true and value is the Boolean(False)) fails:

import apysc as ap

stage: ap.Stage = ap.Stage(
    stage_width=0,
    stage_height=0,
    background_color=ap.Color("#333"),
    stage_elem_id="stage",
)

bool_1: ap.Boolean = ap.Boolean(False)
ap.assert_true(bool_1, msg="Boolean value is not True!")

ap.save_overall_html(dest_dir_path="assert_true_basic_usage_2/")

[assert_true]
Right-side variable name: b_3
Left value: true right value: false
...
Assertion failed: Boolean value is not True!

The following assertion example (assert_true and value is the Int(1) and type_strict is True) will fail:

import apysc as ap

stage: ap.Stage = ap.Stage(
    stage_width=0,
    stage_height=0,
    background_color=ap.Color("#333"),
    stage_elem_id="stage",
)

int_1: ap.Int = ap.Int(1)
ap.assert_true(int_1, type_strict=True, msg="Value is not Boolean(True)!")

ap.save_overall_html(dest_dir_path="assert_true_basic_usage_3/")

[assert_true]
Right-side variable name: i_11
Left value: true right value: 1
...
Assertion failed: Value is not Boolean(True)!

The following assertion example (assert_true and value is the Int(1) and type_strict is False) will pass:

import apysc as ap

stage: ap.Stage = ap.Stage(
    stage_width=0,
    stage_height=0,
    background_color=ap.Color("#333"),
    stage_elem_id="stage",
)

int_1: ap.Int = ap.Int(1)
ap.assert_true(int_1, type_strict=False, msg="Value is not True!")

ap.save_overall_html(dest_dir_path="assert_true_basic_usage_4/")

[assert_true]
Right-side variable name: i_11
Left value: true right value: 1

The following assertion example (assert_false and value is the Boolean(False)) passes:

import apysc as ap

stage: ap.Stage = ap.Stage(
    stage_width=0,
    stage_height=0,
    background_color=ap.Color("#333"),
    stage_elem_id="stage",
)

bool_1: ap.Boolean = ap.Boolean(False)
ap.assert_false(bool_1, msg="Value is not False!")

ap.save_overall_html(dest_dir_path="assert_false_basic_usage_1/")

[assert_false]
Right-side variable name: b_3
Left value: false right value: false

assert_true API

Note: the document build script generates and updates this API document section automatically. Maybe this section is duplicated compared with previous sections.

[Interface signature] assert_true(value: Any, *, type_strict: bool = True, msg: str = '') -> None

[Interface summary]

JavaScript assertion interface for the true condition.

[Parameters]

  • value: *

    • Target value to check.

  • type_strict: bool, default True

    • Whether strictly check actual value or not. For example, if type_strict is True, an integer of 1 fails tests. On the contrary (if type_strict is False), an integer of 1 passes tests.

  • msg: str, optional

    • Message to display when assertion failed.

[Examples]

>>> import apysc as ap
>>> int_val: ap.Int = ap.Int(10)
>>> boolean: ap.Boolean = int_val == 10
>>> ap.assert_true(boolean)

assert_false API

Note: the document build script generates and updates this API document section automatically. Maybe this section is duplicated compared with previous sections.

[Interface signature] assert_false(value: Any, *, type_strict: bool = True, msg: str = '') -> None

[Interface summary]

JavaScript assertion interface for the false condition.

[Parameters]

  • value: *

    • Target value to check.

  • type_strict: bool, default True

    • Whether strictly check actual value or not. For example, if type_strict is True, an integer of 0 fails tests. On the contrary (if type_strict is False), an integer of 0 passes tests.

  • msg: str, optional

    • Message to display when assertion failed.

[Examples]

>>> import apysc as ap
>>> int_val: ap.Int = ap.Int(10)
>>> boolean: ap.Boolean = int_val == 11
>>> ap.assert_false(boolean)