Apep-std-vars

Common generators and combinators for working with variables in Apep Javascript text generation library.

Usage

$ npm install apep-std-vars

You can either use apep-std-vars as its own include:

const pep = require('apep');
const pep_vars = require('apep-std-vars');

const p = pep_vars.store(...);

Or by extending an Apep instance:

let pep = require('apep');
pep = require('apep-std-vars')(pep);

const p = pep.store(...);

Extension does not alter the original Apep include but creates a simple proxy that also has the std-var functionality.

Documentation

clear(name)

Delete a variable.

• name - Variable name.

setFrom(name, generator)

Set the variable name to the result of generator.

• name - Variable name.
• generator - Generator run to produce the value.

const name = pep_vars.setFrom('name', pep.choice('Alice', 'Bob'))

const p = pep.seq(
    'Affirmative, ', name '. I read you. ',
    'Im sorry, ', pep.get('name'), ". Im afraid I cant do that.");

p.run() === "Affirmative, Dave. I read you. Im sorry Dave. Im afraid I cant do that."
p.run() === "Affirmative, Alice. I read you. Im sorry Alice. Im afraid I cant do that."

Always stores value as strings. The output of multiple yielding generators are joined together into a single string value. setFrom yields this combined value as its result.

use setFromCombined if you need to store non-string values.

setFromCombined(f, z, name, generator)

Same behavior as setFrom, but combines multiple yielded values with an accumulator function.

• f - Accumulator function to reduce multiple yields from generator to a single value.
• z - Initial value for accumulator.
• name - Variable name.
• generator - Generator run to produce the value.

store(name, generator)

Get the currently stored value of a variable or compute it with a generator.

• name - Variable name.
• generator - Generator run to produce the value.

// Make sure we always use the same name after computing it.
const name = pep_vars.store('name', pep.choice('Alice', 'Bob'))

const p = pep.seq(
    'Affirmative, ', name '. I read you. ',
    'Im sorry, ', name, ". Im afraid I cant do that.");

p.run() === "Affirmative, Dave. I read you. Im sorry Dave. Im afraid I cant do that."
p.run() === "Affirmative, Alice. I read you. Im sorry Alice. Im afraid I cant do that."

Always stores value as strings. The output of multiple yielding generators are joined together into a single string value. store yields this combined value as its result.

const v = pep_vars.store('joined_var',
    pep.seq(
        pep.lit(1.2),
        pep.lit({}),
        pep.lit(null)));

const p = pep.seq(v, v)

Array.from(p) === ['1.2[Object object]null', '1.2[Object object]null'];

Use storeCombined if you need to store non-string values.

storeCombined(f, z, name, generator)

Same behavior as store, but combines multiple yielded values with an accumulator function.

• f - Accumulator function to reduce multiple yields from generator to a single value.
• z - Initial value for accumulator.
• name - Variable name.
• generator - Generator run to produce the value.