$☠️--math-steps: 32 !default; 
@function pow($x, $exponent, $steps: $☠️--math-steps) {
    $exp1: round($exponent);                
    $exp2: $exponent - $exp1;               
    $pow1: ☠️--pow-int($x, $exp1);          
    @if $exp2 == 0 { @return $pow1; }       
    @else if $x == 0 and $exponent > 0 { @return 0; }   
    @else {
        $y: ☠️--log($x, $steps) * $exp2;
        $pow2: ☠️--exp-taylor-0($y, $steps);
        @return $pow1 * $pow2;
    }
}

//  private helper functions
@function ☠️--log($x, $steps: $☠️--math-steps) {
    $log10: 2.302585092994046; 
    $approx: ☠️--log10-approx($x);
    // $y is in range [1, 10]
    $y: $x / ☠️--pow-int(10, $approx);
    @return $approx * $log10 + ☠️--log-taylor-1($y, $steps);
}

@function ☠️--pow-int($base, $exponent) {
    @if $exponent < 0 { @return 1 / ☠️--pow-int($base, -$exponent); } 
    @else if $exponent == 0 { @return 1; } 
    @else if $exponent == 1 { @return $base; } 
    @else {
        $exp: floor($exponent / 2);
        $pow: ☠️--pow-int($base, $exp);
        @if $exp * 2 == $exponent { @return $pow * $pow; } 
        @else { @return $pow * $pow * $base; }
    }
}
@function ☠️--log10-approx($x) {
    @if $x <= 0 { @error 'cannot calculate log of #{$x}'; } 
    // choose the smaller option (-1) because it yields better results in log().
    @else if $x >= 1 { @return str-length(inspect(round($x))) - 1; } 
    @else { @return -1 * str-length(inspect(round(1 / $x))); }
}
@function ☠️--exp-taylor-0($x, $steps) {
    $item: 1;
    $result: 1;
    @for $i from 1 to $steps {
        $item: $item * $x / $i;
        $result: $result + $item;
    }
    @return $result;
}
@function ☠️--log-taylor-1($x, $steps) {
    $z: ($x - 1) / ($x + 1);
    $power: $z;
    $result: $z;
    @for $i from 1 to $steps {
        $power: $power * $z * $z;
        $result: $result + $power / (2 * $i + 1);
    }
    @return 2 * $result;
}

golden-scale {
    $r: 1.61803398874989484820; // ratio: phi
    $n: 2;                      // notes: number of notes 
    @for $i from -5 through 5 {
        scale-#{$i+5}: pow($r, $i/$n);
    }
}