taskwarrior/docs/rfcs/cli.md
2022-05-25 21:17:36 -04:00

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---
title: "Taskwarrior - Command Line Interface"
---
## Work in Progress
This design document is a work in progress, and subject to change. Once
finalized, the feature will be scheduled for an upcoming release.
# CLI Syntax Update
The Taskwarrior command line syntax is being updated to allow more consistent
and predictable results, while making room for new features.
Adding support for arbitrary expressions on the command line has become
complicated because of the relaxed syntax of Taskwarrior. While the relaxed
syntax allows for a very expressive command line, it also creates ambiguity for
the parser, which needs to be reduced.
With some limited and careful changes it will be possible to have a clear and
unambiguous command line syntax, which means a predictable and deterministic
experience.
It should be stated that for straightforward and even current usage patterns,
the command line will likely not change for you. Another goal is to not require
changes to 3rd-party software, where possible. Only the more advanced and as-yet
unintroduced features will require a more strict syntax. This is why now is an
ideal time to tighten the requirements.
## Argument Types
The argument types supported remain the same, adding some new constructs.
--------------------------------------- ---------------------------------------
Config file override `rc:<file>`
Configuration override `rc:<name>:<value>` Literal value\
`rc:<name>=<value>` Literal value\
`rc:<name>:=<value>` Calculated value
Tag `+<tag>`\
`-<tag>`\
`'+tag one'` Multi-word tag
Attribute modifier `rc:<name>.<modifier>:<value>`\
Modifier is one of:\
`before`\
`after`\
`under`\
`over`\
`above`\
`below`\
`none`\
`any`\
`is`\
`isnt`\
`equals`\
`not`\
`contains`\
`has`\
`hasnt`\
`left`\
`right`\
`startswith`\
`endswith`\
`word`\
`noword`
Search pattern `/<pattern>/`
Substitution `/<from>/<to>/`\
`/<from>/<to>/g`
Command `add`\
`done`\
`delete`\
`list`\
etc.
Separator `--`
ID Ranges `<id>[-&ltid>][,<id>[-&ltid>]...]`
UUID `<uuid>`
Everything Else `<word>`\
`'<word> <word> ...'`
--------------------------------------- ---------------------------------------
## New Command Line Rules
Certain command line constructs will no longer be supported, and this is imposed
by the new rules:
1. Each command line argument may contain only one instance of one argument
type, unless that type is `<word>`.
task add project:Home +tag Repair the thing # Good
task add project:Home +tag 'Repair the thing' # Good
task add 'project:Home +tag Repair the thing' # Bad
Putting two arguments into one quoted arg makes that arg a `<word>`.
2. If an argument type contains spaces, it must either be quoted or escaped.
task add project:'Home & Garden' ... # Good
task add 'project:Home & Garden' ... # Good
task add project:Home\ \&\ Garden ... # Good
task add project:Home' & 'Garden ... # Good
task add project:Home \& Garden ... # Bad
The parser will not combine multiple arguments, for example:
task '/one two/' list # Good
task /one two/ list # Bad
task /'one two'/ list # Bad, unless ' is part of the pattern
3. By default, *no* calculations are made, unless the `:=` eval operator is
used, and if so, the whole argument may need to be quoted or escaped to
satisfy Rule 1.
task add project:3.project+x # Literal
task add project:=3.project+x # DOM reference + concatenation
4. Bare word search terms are no longer supported. Use the pattern type
argument instead.
task /foo/ list # Good
task foo list # Bad
5. Expressions must be a series of arguments, not a quoted string.
task urgency \< 5.0 list # Good
task 'urgency < 5.0 list' # Bad
## Other Changes
Aside from the command line parser, there are other changes needed:
- Many online documents will need to be modified.
- Filters will be automatically parenthesized, so that every command line will
now looke like:
task [overrides] [(cli-filter)] [(context-filter)] [(report-filter)] command [modifications]
- There will be more errors when the command line is not understood.
- Ambiguous ISO date formats are dropped.
YYYYMMDD # Bad
YYYY-MM-DD # Good
hhmmss # Bad
hh:mm:ss # Good
- The tutorial videos will be even more out of date, and will be replaced by a
large number of smaller demo \'movies\'.