Plan.is_name: def of ezx@1.11.0.0
Import: import ezx@1.11.0.0/src/pub/plan.bend as Plan
Lines 45-59 of ezx@1.11.0.0/src/pub/plan.bend: https://jend.leeeet.dev/read.txt?path=ezx@1.11.0.0/src/pub/plan.bend&start_line=45&end_line=59

import Base
import ezx@1.11.0.0/src/git/git.bend as G

# whether a line is a `0x` package name and nothing else. Anchored at both
# ends: the prefix, the exact length, and every character after the prefix one
# a lowercase hex digest may hold. `git/git.bend` already walks a hex string
# for `is_rev`, and its walk stops at the first character that is not hex.
#
# The lines bend prints around its answer fail this, and `pub/LAWS.bend` says
# so for the two that hold the name, rather than leaving it to a reading of
# bend's source: `publishing N files, ... as 0x... (mining its proof of work)`
# and `import 0x.../entry.bend as Name` each start with something that is not
# `0x`. The terms notice and the license line bend 2.0.27 prints first
# (`Publishing to BendHub: ...`, `License: ...`) start with a word too.
def is_name(+word: String) -> Bool:
  Bool.and(String.starts_with(word, "0x"),
    Bool.and(Nat.is_eq(String.length(word), name.length()),
      G.hex.all(String.to_list(String.drop(word, 2n)))))

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_eq
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.drop
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.length
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.starts_with
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.to_list
  https://jend.leeeet.dev/definition.txt?path=ezx@1.11.0.0/src/git/git.bend&name=hex.all
  https://jend.leeeet.dev/definition.txt?path=ezx@1.11.0.0/src/pub/plan.bend&name=name.length