Reader, had I the space to write at will,
I should, if only briefly, sing a praise
of that sweet draught. Would I were drinking still!
But I have filled all the pages planned
for this, my second, canticle, and Art
pulls at its iron bit with iron hand.

[S’io avessi, lettor, più lungo spazio
da scrivere, i’ pur cantere’ in parte
lo dolce ber che mai non m’avria sazio;
ma perché piene son tutte le carte
ordite a questa cantica seconda,
non mi lascia più ir lo fren de l’arte.]

Dante Alighieri (1265-1321) Italian poet

The Divine Comedy [Divina Commedia], Book 2 “Purgatorio,” Canto 33, l. 136ff (3.136-141) (1314) [tr. Ciardi (1961)]
    (Source)

On drinking from the Eunoë, Dante gets meta, breaking the Fourth Wall and, having self-imposed limits on the number of cantos per book and lines in each canto, he uses "Art" as an excuse to draw toward a conclusion.

On the other hand, Sayers notes that Dante "is almost unique among medieval writers" in restraining his writing: "one of the reasons for his enduring readableness."

(Source (Italian)). Alternate translations:

If breath and vigour, by indulgent Heav'n,
To sing this bev'rage of the Gods were giv'n,
What holy rapture would exalt my Song!
To tell the unexhausted sweets that flow
From that blest Fountain o'er the Vale below.
And warm, with new desire, the votive Throng!
But now the Muse has run her fatal round,
And mark'd her Circle to the Second Bound.
[tr. Boyd (1802), st. 26-27]

Were further space allow’d,
Then, Reader, might I sing, though but in part,
That beverage, with whose sweetness I had ne’er
Been sated. But, since all the leaves are full,
Appointed for this second strain, mine art
With warning bridle checks me.
[tr. Cary (1814)]

Reader, had I but longer space to write,
I might describe to thee, in part, the taste
Of draught that's ever sweet, nor waste
The time; but leaves are all already full
Appointed for the second canticle,
Nor curb nor rein permit me use the will.
[tr. Bannerman (1850)]

If, Reader, I possessed a longer space
For writing it, I yet would sing in part
Of the sweet draught that ne'er would satiate me;
But inasmuch as full are all the leaves
Made ready for this second canticle,
The curb of art no farther lets me go.
[tr. Longfellow (1867)]

If I had, reader, longer space to write, I should sing, at all events in part, the sweet draught which never would have sated me; but, for that all the sheets put in frame for this second Canticle are full, the bridle of my art lets me go no further.
[tr. Butler (1885)]

Reader, if longer space to me were rated
For writing, I would strive to sing in part
That draught so sweet, which never could have sated.
But since is now completely filled the chart
Allotted for this second book, there leaves
No power to wander more the curb of Art.
[tr. Minchin (1885)]

If I had, Reader, longer space for writing I would yet partly sing the sweet draught which never would have sated me. But, because all the leaves destined for this second canticle are full, the curb of my art lets me go no further.
[tr. Norton (1892)]

If, reader, I had greater space for writing, I would sing, at least in part, of the sweet draught which never would have sated me;
but forasmuch as all the pages ordained for this second canticle are filled, the curb of art no further lets me go.
[tr. Okey (1901)]

If, reader, I had more space to write I should sing but in part the sweet draught which never would have sated me; but since all the sheets prepared for this second cantica are full the curb of art does not let me go farther.
[tr. Sinclair (1939)]

If, Reader, for the writing were more space,
That sweet fount, whence I ne'er could drink my fill,
Would I yet sing, though in imperfect praise.
But seeing that for this second canticle
The paper planned is full to the last page,
The bridle of art must needs constrain my will.
[tr. Binyon (1943)]

If for my writing, Reader, I'd more space,
I'd sing -- at least in part -- those sweets my heart
Might aye have drunk nor e'er known weariness;
But since I've filled the pages set apart
For this my second cantique, I'll pursue
No further, bridled by the curb of art.
[tr. Sayers (1955)]

If, reader, I had greater space for writing
I would yet partly sing the sweet draught
which never would have sated me.
but since all the pages ordained
for this second canticle are filled,
the curb of art lets me go no further.
[tr. Singleton (1973)]

Reader, if I had space to write more words,
I'd sing, at least in part, of that sweet draught
which never could have satisfied my thirst;
But now I have completed every page
planned for my poem's second canticle --
I am checked by the bridle of my art!
[tr. Musa (1981)]

If, reader, I had room to write more,
My poem could still not tell you everything
About the sweet drink of which I could never have had enough.
But since all the pages designed for this
Second part of the poem have been filled,
The rules of art stop me at this point.
[tr. Sisson (1981)]

If, reader, I had ampler space in which
to write, I'd sing -- though incompletely -- that
sweet draught for which my thirst was limitless;
but since all of the pages pre-disposed
for this, the second canticle, are full,
the curb of art will not let me continue.
[tr. Mandelbaum (1982)]

Reader, if I had more space to write, I would speak, partially at least, about that sweet drink, which would never have sated me: but because all the pages determined for the second Canticle are full, the curb of art lets me go no further.
[tr. Kline (2002)]

If, reader, I had more space to write, I would continue to sing in part the sweet drink that could never satiate me,
but because all the pages are filled that have been laid out for this second canticle, the bridle of art permits me to go no further.
[tr. Durling (2003)]

If, reader, I'd more space in which to write,
then I should sing in part about that drink,
so sweet I’d never have my fill of it.
However, since these pages now are full,
prepared by rights to take the second song,
the reins of art won't let me pass beyond.
[tr. Kirkpatrick (2007)]

If, reader, I had more ample space to write,
I should sing at least in part the sweetness
of the drink that never would have sated me,
but, since all the sheets
readied for this second canticle are full,
the curb of art lets me proceed no farther.
[tr. Hollander/Hollander (2007)]

O reader, if I had the space to tell you
More, I'd sing something about that sweetest
Drink, no quantity of which could ever
End my thirst, but because the pages meant
For this canto are already filled, my art prevents me,
Affirming limits I am forced to meet.
[tr. Raffel (2010)]