SwiftCompactor

Formatters for the concise display of Numbers, Currency, and Time Intervals

Why SwiftCompactor? First, use where precision isn’t critical, but space is at a premium. Second, compact values like $8.6M are more easily grasped over values like $8,603,842.35, lowering the cognitive load for the user.

Available as an open source Swift library to be incorporated in other apps.

Compactor is part of the OpenAlloc family of open source Swift software tools.

let c = NumberCompactor()
print(c.string(from: 1_234_567))

=> "1.2M"

By default, values will show up to one fractional decimal point of the value, rounded if necessary.

• ifZero (default: (String?)nil) - if nil and value is zero, a zero value will be shown. If !nil and value is zero, the specified string value will be shown
• roundSmallToWhole (default: false) - if true, fractional parts excluded from values within -100...100

For more detail see the Binary Prefix page at Wikipedia.

let c = CurrencyCompactor()
print(c.string(from: 1_234_567))

=> "$1.2M"

By default, values within -100...100 will have no fractional part, and are rounded where necessary. Outside that one fractional decimal point of the value is shown, rounded if necessary.

• ifZero (default: (String?)nil) - if nil and value is zero, a zero value will be shown. If !nil and value is zero, the specified string value will be shown
• roundSmallToWhole (default: true) - if true, fractional parts excluded from values within -100...100

Note that roundSmallToWhole is true by default, because $1.1 looks awkward when we’re accustomed to fractions in pennies.

The same as used with NumberCompactor().

With TimeCompactor() you provide it a TimeInterval value to be transformed into a string value.

let c = TimeCompactor()
print(c.string(from: 1_234_567))

=> "14.3d"

let f = TimeCompactor(style: .full)
print(f.string(from: 1_234_567))

=> "14.3 days"

By default, values will show up to one fractional decimal point of the value, rounded if necessary.

• ifZero (default: (String?)nil) - if nil and value is zero, a zero value will be shown. If !nil and value is zero, the specified string value will be shown
• style (default: .short) - the style of suffix used
• roundSmallToWhole (default: false) - if true, fractional parts excluded from values within -100...100

The suffix will depend on the style, of which there is currently .short (default), .medium, and .full.

Note that .medium and .full include plural forms.

Swift open-source libraries (by the same author):

• AllocData - standardized data formats for investing-focused apps and tools
• FINporter - library and command-line tool to transform various specialized finance-related formats to the standardized schema of AllocData
• SwiftModifiedDietz - A tool for calculating portfolio performance using the Modified Dietz method
• SwiftNiceScale - generate 'nice' numbers for label ticks over a range, such as for y-axis on a chart
• SwiftRegressor - a linear regression tool that’s flexible and easy to use
• SwiftSeriesResampler - transform a series of coordinate values into a new series with uniform intervals
• SwiftSimpleTree - a nested data structure that’s flexible and easy to use

And open source apps using this library (by the same author):

• FlowAllocator - portfolio rebalancing tool for macOS
• FlowWorth - a new portfolio performance and valuation tracking tool for macOS

Copyright 2021, 2022 OpenAlloc LLC

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Contributions are welcome. You are encouraged to submit pull requests to fix bugs, improve documentation, or offer new features.

The pull request need not be a production-ready feature or fix. It can be a draft of proposed changes, or simply a test to show that expected behavior is buggy. Discussion on the pull request can proceed from there.

Contributions should ultimately have adequate test coverage. See tests for current entities to see what coverage is expected.