gopprint

An implementation of Kiselyov et al's pretty printing algorithm in Go.

Pretty printing occurs in two global phases. Rather than try to print some random tree directly, which could get quite ugly quite quickly, we build a "pretty printer document" out of some very simple primitives. These primitives (and our algorithm) are due to D.C. Oppen originally and later Kiselyov et al. Oppen's original formulation had Text, LineBreak, Concat, and Group. I generalized LineBreak to cond_t which became our cond_t because we need to do more sophisticated breaks, and I added nest_t for controllable indentation.

• http://dl.acm.org.sci-hub.io/citation.cfm?id=357115 Oppen, D.C.: Prettyprinting. ACM Trans. Program. Lang. Syst. 2 (1980) 465–483. Not available online without an ACM subscription.
• http://okmij.org/ftp/continuations/PPYield/yield-pp.pdf Kiselyov, O., Peyton-Jones, S. and Sabry, A.: Lazy v. Yield: Incremental, Linear Pretty-printing.