Lessons · Advanced

A rhythm with holes in it

A tango whose rhythm is written three times, and its notes once

% Every duration in this language has been stuck to the note that
% carries it. '_2' lengthens a note, '/2' shortens one, and there has
% been no way to say a RHYTHM on its own and pour notes into it.
%
% '$1' is a SLOT. A rule with slots in it is a shape with holes, and the
% holes take notes. Here is the HABANERA — long, short, two even — the
% cell under a thousand tangos, with no notes in it at all:
 
bpm 100
meter 4
unit 1/4
key a4 harm
 
Habanera ::= $1 _3 $2 $3 _2 $4 _2
 
% heard on one note, so the shape is all there is to hear
Habanera(.1 .1 .1 .1)*2
 
 
% Now pour a bass into it. The cell says WHEN, the line says WHAT, and
% neither knows anything about the other: A A E E, the tango ground.
 
Gi ::= .1 .1 .5 .5
 
Habanera(Gi)*2
 
% The same four notes under an even tread. Nothing in Gi moved — only
% the cell it fell into. That is the whole idea.
 
Even ::= $1 _2 $2 _2 $3 _2 $4 _2
 
Even(Gi)*2
 
 
% A line spreads into the slots, and the cell CYCLES until it runs out,
% so one cell can carry a whole phrase. Four grounds, eight bars of
% bass, and the rhythm written once.
 
Giv ::= .4 .4 .1 .1
GV  ::= .5 .5 .2 .2
GVI ::= .6 .6 .3 .3
 
assert Habanera(Gi) == .1 _3 .1 .5 _2 .5 _2
 
Habanera(Gi Gi Giv GV)
 
 
% Because the rhythm and the line are separate things now, either can be
% turned WITHOUT the other — which nothing in the language could say
% before. A mark BEFORE the paren belongs to the cell; a mark inside
% belongs to the line.
 
% the same ground, its rhythm played backwards
Habanera~(Gi Gi)
 
% the same rhythm, the ground walking backwards
Habanera(Gi~ Gi)
 
 
% A slot may repeat, and a template may itself be a polymetric
% structure — so a GROOVE can span two staves at once. '$5' sounds twice
% here, once in each half of the bar, while the bass takes the habanera
% underneath it.
 
Groove ::= {$1 _3 $2 $3 _2 $4 _2, $5 _4 $5 _4}
 
Groove(.1 .1 .5 .5 3)
Groove(.1 .1 .5 .5 3 .1 .1 .5 .5 4)
 
 
% THE SONG. Three cells carry all of it. The habanera is the bass of the
% outer sections; the TRESILLO — three, three, two — is the bass of the
% middle one, the same ground heard limping; and the SIGH is the tune's
% own rhythm, long then three shorter, four notes to the bar.
%
% Nothing below writes a duration twice. Every note in the piece arrives
% through one of these three shapes.
 
Tresillo ::= $1 _3 $2 _3 $3 _2
Sigh     ::= $1 _6 $2 _2 $3 _4 $4 _4
 
Ti  ::= .1 .5 .1
Tiv ::= .4 .1 .4
TV  ::= .5 .2 .5
TVI ::= .6 .3 .6
 
TuneA ::= 5 6 5 4 3 4 3 .7 4 6 4 3 2 .7 2 5 5 6 5 4 3 4 3 .7 2 .7 2 4 3 2 1 1
TuneB ::= '1 7 6 5 6 5 4 3 4 5 6 5 2 4 3 2 '1 7 6 5 6 5 4 3 4 3 2 .7 1 1 1 1
TuneC ::= 1 1 2 .7 1 3 2 1 3 5 3 2 1 .7 1 1
 
Sigh(TuneA)
 
 
% The bass of each section is one call: the harmony written as grounds,
% poured through the cell. The coda takes the habanera BACKWARDS, so the
% groove that opened the piece limps home reversed under a tune that
% still walks forwards.
 
BassA ::= Habanera(Gi Gi Gi Gi Giv Giv GV GV Gi Gi Gi Gi GV GV Gi Gi)
BassB ::= Tresillo(TVI TVI TVI TVI Tiv Tiv Tiv Tiv TV TV TV TV Ti Ti Ti Ti)
BassC ::= Habanera~(Gi Gi Gi Gi GV GV Gi Gi)
 
Intro ::= Habanera(Gi Gi Gi Gi GV GV Gi Gi)
Verse ::= {Sigh(TuneA), BassA}
Turn  ::= {Sigh(TuneB), BassB}
Coda  ::= {Sigh(TuneC), BassC}
Close ::= {1, 3, 5, .1} _16
 
% thirty-three bars, and the rhythm is written in three lines
Intro
Verse
Turn
Verse
Coda
Close

% Every duration in this language has been stuck to the note that
% carries it. '_2' lengthens a note, '/2' shortens one, and there has
% been no way to say a RHYTHM on its own and pour notes into it.
%
% '$1' is a SLOT. A rule with slots in it is a shape with holes, and the
% holes take notes. Here is the HABANERA — long, short, two even — the
% cell under a thousand tangos, with no notes in it at all:

bpm 100
meter 4
unit 1/4
key a4 harm

Habanera ::= $1 _3 $2 $3 _2 $4 _2

% heard on one note, so the shape is all there is to hear
Habanera(.1 .1 .1 .1)*2

% Now pour a bass into it. The cell says WHEN, the line says WHAT, and
% neither knows anything about the other: A A E E, the tango ground.

Gi ::= .1 .1 .5 .5

Habanera(Gi)*2

% The same four notes under an even tread. Nothing in Gi moved — only
% the cell it fell into. That is the whole idea.

Even ::= $1 _2 $2 _2 $3 _2 $4 _2

Even(Gi)*2

% A line spreads into the slots, and the cell CYCLES until it runs out,
% so one cell can carry a whole phrase. Four grounds, eight bars of
% bass, and the rhythm written once.

Giv ::= .4 .4 .1 .1
GV  ::= .5 .5 .2 .2
GVI ::= .6 .6 .3 .3

assert Habanera(Gi) == .1 _3 .1 .5 _2 .5 _2

Habanera(Gi Gi Giv GV)

% Because the rhythm and the line are separate things now, either can be
% turned WITHOUT the other — which nothing in the language could say
% before. A mark BEFORE the paren belongs to the cell; a mark inside
% belongs to the line.

% the same ground, its rhythm played backwards
Habanera~(Gi Gi)

% the same rhythm, the ground walking backwards
Habanera(Gi~ Gi)

% A slot may repeat, and a template may itself be a polymetric
% structure — so a GROOVE can span two staves at once. '$5' sounds twice
% here, once in each half of the bar, while the bass takes the habanera
% underneath it.

Groove ::= {$1 _3 $2 $3 _2 $4 _2, $5 _4 $5 _4}

Groove(.1 .1 .5 .5 3)
Groove(.1 .1 .5 .5 3 .1 .1 .5 .5 4)

% THE SONG. Three cells carry all of it. The habanera is the bass of the
% outer sections; the TRESILLO — three, three, two — is the bass of the
% middle one, the same ground heard limping; and the SIGH is the tune's
% own rhythm, long then three shorter, four notes to the bar.
%
% Nothing below writes a duration twice. Every note in the piece arrives
% through one of these three shapes.

Tresillo ::= $1 _3 $2 _3 $3 _2
Sigh     ::= $1 _6 $2 _2 $3 _4 $4 _4

Ti  ::= .1 .5 .1
Tiv ::= .4 .1 .4
TV  ::= .5 .2 .5
TVI ::= .6 .3 .6

TuneA ::= 5 6 5 4 3 4 3 .7 4 6 4 3 2 .7 2 5 5 6 5 4 3 4 3 .7 2 .7 2 4 3 2 1 1
TuneB ::= '1 7 6 5 6 5 4 3 4 5 6 5 2 4 3 2 '1 7 6 5 6 5 4 3 4 3 2 .7 1 1 1 1
TuneC ::= 1 1 2 .7 1 3 2 1 3 5 3 2 1 .7 1 1

Sigh(TuneA)

% The bass of each section is one call: the harmony written as grounds,
% poured through the cell. The coda takes the habanera BACKWARDS, so the
% groove that opened the piece limps home reversed under a tune that
% still walks forwards.

BassA ::= Habanera(Gi Gi Gi Gi Giv Giv GV GV Gi Gi Gi Gi GV GV Gi Gi)
BassB ::= Tresillo(TVI TVI TVI TVI Tiv Tiv Tiv Tiv TV TV TV TV Ti Ti Ti Ti)
BassC ::= Habanera~(Gi Gi Gi Gi GV GV Gi Gi)

Intro ::= Habanera(Gi Gi Gi Gi GV GV Gi Gi)
Verse ::= {Sigh(TuneA), BassA}
Turn  ::= {Sigh(TuneB), BassB}
Coda  ::= {Sigh(TuneC), BassC}
Close ::= {1, 3, 5, .1} _16

% thirty-three bars, and the rhythm is written in three lines
Intro
Verse
Turn
Verse
Coda
Close

running…edit it — it re-runs as you type

Opening…

A rhythm with holes in it · Pattern Engine