source: code/trunk/vendor/github.com/yosssi/gcss/line.go@ 75

package gcss

import (
        "fmt"
        "strings"
)

const unicodeSpace = 32

const indentTop = 0

// line represents a line of codes.
type line struct {
        no     int
        s      string
        indent int
}

// isEmpty returns true if the line's s is zero value.
func (ln *line) isEmpty() bool {
        return strings.TrimSpace(ln.s) == ""
}

// isTopIndent returns true if the line's indent is the top level.
func (ln *line) isTopIndent() bool {
        return ln.indent == indentTop
}

// childOf returns true if the line is a child of the parent.
func (ln *line) childOf(parent element) (bool, error) {
        var ok bool
        var err error

        switch pIndent := parent.Base().ln.indent; {
        case ln.indent == pIndent+1:
                ok = true
        case ln.indent > pIndent+1:
                err = fmt.Errorf("indent is invalid [line: %d]", ln.no)
        }

        return ok, err
}

// isDeclaration returns true if the line is a declaration.
func (ln *line) isDeclaration() bool {
        _, _, err := declarationPV(ln)
        return err == nil
}

// isAtRule returns true if the line is an at-rule.
func (ln *line) isAtRule() bool {
        return strings.HasPrefix(strings.TrimSpace(ln.s), atMark)
}

// isVariable returns true if the line is a variable.
func (ln *line) isVariable() bool {
        if !ln.isTopIndent() {
                return false
        }

        _, _, err := variableNV(ln)

        return err == nil
}

// isMixinDeclaration returns true if the line is a mixin declaration.
func (ln *line) isMixinDeclaration() bool {
        if !ln.isTopIndent() {
                return false
        }

        _, _, err := mixinNP(ln, true)

        return err == nil
}

// isMixinInvocation returns true if the line is a mixin invocation.
func (ln *line) isMixinInvocation() bool {
        if ln.isTopIndent() {
                return false
        }

        _, _, err := mixinNP(ln, false)

        return err == nil
}

// isComment returns true if the line is a comment.
func (ln *line) isComment() bool {
        return strings.HasPrefix(strings.TrimSpace(ln.s), doubleSlash)
}

// newLine creates and returns a line.
func newLine(no int, s string) *line {
        return &line{
                no:     no,
                s:      s,
                indent: indent(s),
        }
}

// indent returns the string's indent.
func indent(s string) int {
        var i int

        for _, b := range s {
                if b != unicodeSpace {
                        break
                }
                i++
        }

        return i / 2
}