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Scalar Parameter Types

Scalar parameters define single-value fields in a definition's parameter schema. Each constructor returns a *Param that maps directly to a CUE primitive type and can be chained with modifiers like .Optional(), .Default(), and .Description().

defkit.String()​

A UTF-8 string parameter. Optional by default — the field is emitted as field?: string. Use .Default(v) to emit a non-optional field with a default (field: *v | string), or .Mandatory() for a non-optional field without a default (field: string).

Go — defkit
image   := defkit.String("image")              // optional by default
tag     := defkit.String("tag").Default("latest")
comment := defkit.String("comment").Optional() // explicitly optional
CUE — generated
image?:   string
tag:      *"latest" | string
comment?: string

defkit.Int()​

A 64-bit integer parameter. Supports .Min(n) and .Max(n) for inclusive range constraints.

Go — defkit
replicas := defkit.Int("replicas").Default(1).Min(1).Max(50)
port     := defkit.Int("port")
CUE — generated
replicas: *1 | int & >=1 & <=50
port?:    int

defkit.Bool()​

A boolean parameter. .Default(true) or .Default(false) sets the CUE default value.

Go — defkit
enable := defkit.Bool("enable").Default(true)
debug  := defkit.Bool("debug").Default(false)
CUE — generated
enable: *true  | bool
debug:  *false | bool

defkit.Float()​

A floating-point number parameter. Supports .Min(f) and .Max(f) for range constraints. Generates the CUE number type.

Go — defkit
ratio  := defkit.Float("ratio").Default(0.5).Min(0.0).Max(1.0)
weight := defkit.Float("weight")
CUE — generated
ratio:   *0.5 | number & >=0 & <=1
weight?: number

defkit.Enum()​

A string parameter constrained to a fixed set of allowed values. Use .Values() — not .Enum() — to specify the allowed set (current convention as of defkit API update).

Go — defkit
// Use .Values(), not .Enum() — current convention
pullPolicy := defkit.Enum("imagePullPolicy").
    Values("Always", "Never", "IfNotPresent").
    Default("IfNotPresent")
CUE — generated
imagePullPolicy: *"IfNotPresent" | "Always" | "Never"
tip

Combine .Values() with .Default() to pre-select one of the allowed values. The default appears first in the CUE disjunction with the * marker.